Morphology and Biochemistry of Diploid and Androgenetic Haploid (Merogonic) Hybrids

  • P. S. Chen
  • F. Baltzer


Sea urchin hybrids have often been used to study nucleo-cytoplasmic interaction during embryonic development. In diploid hybrids the sperm nucleus of one species is introduced into the egg of another species, while in haploid merogonic hybrids anucleate egg fragments are crossfertilized. In the former the egg contains 2 pronuclei of different species, and in the latter a male pronucleus is enclosed by foreign cytoplasm without a second haploid nucleus. Both combinations often result in disharmonic interaction between nucleus and cytoplasm, leading sooner or later to developmental arrest and death of the embryo. It is evident that analysis of the cytologic behavior and morphogenetic patterns of these hybrids provide us with valuable information about the basic mechanism of embryonic development.


Parental Species Gastrula Stage Hybrid Embryo Paternal Genome Maternal Control 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. BADMAN, W.W., BROOKBANK, J.W., 1970. Serological studies of 2 hybrid sea urchins. Develop. Biol. 21, 243–256.PubMedGoogle Scholar
  2. BALTZER, F., 1909. Die Chromosomen von Strongylocentrotus lividus and Echinus microtuberculatus. Arch. Zellforsch. 2, 549–632.Google Scholar
  3. BALTZER, F., 1910. Über die Beziehung zwischen Chromatin und der Entwicklung und Vererbungsrichtung bei Echinodermusbastarden. Arch. Zellforsch. 5, 497–621.Google Scholar
  4. BALTZER, F., BERNHARD, M., 1955. Weitere Beobachtungen über Letalität und Vererbungsrichtung beim Seeigelbastard Paracentrotus ♀ x Arbacia ♂. Exp. Cell Res. Suppl. 3, 16–26.Google Scholar
  5. BALTZER, F., CHEN, P.S., 1960. Über das zytologische Verhalten und die Synthese der Nukleinsäuren bei den Seeigelbastarden Paracentrotus ♀ x Arbacia ♂ und Paracentrotus ♀ x Sphaerechinus♂. Rev. Suisse Zool. 67, 183–194.Google Scholar
  6. BALTZER, F., CHEN, P.S., 1965. A study of DNA synthesis in sea urchin hybrids by the incorporation of H3-thymidine. Experientia 21, 194–196.PubMedGoogle Scholar
  7. BALTZER, F., CHEN, P.S., TARDENT, P., 1961. Embryonalentwicklung, DNS-Synthese und Respiration des Bastards Arbacia ♀ x Paracentrotus, mit Vergleichen zu anderen Seeigelbastarden. Arch. Julius Klaus-Stift. Vererbungsforsch. Sozialanthropol. Rassenhyg. 36, 126–135.Google Scholar
  8. BALTZER, F., CHEN, P.S., WHITELEY, A.H., 1958. Biochemical studies on sea urchin hybrids. Exp. Cell Res. Suppl. 6, 192–209.Google Scholar
  9. BALTZER, F., HARDING, C., LEHMAN, H.E., BOPP, P., 1954. Über die Entwicklungshemmungen der Seeigelbastarde Paracentrotus ♀ x Arbacia und Psammechinus ♀ x Arbacia . Rev. Suisse Zool. 61, 402–416.Google Scholar
  10. BALTZER, F., TARDENT, P., CHEN, P.S., 1967. About the DNA-synthesis during the early development of Paracentrotus lividus, Arbacia lixula and their hybrids. Experientia 23, 777–779.PubMedGoogle Scholar
  11. BARRETT, D., ANGELLO, G.M., 1969. Maternal characteristics of hatching enzymes in hybrid sea urchin embryos. Exp. Cell Res. 57, 159–166.PubMedGoogle Scholar
  12. BERG, W.E., 1950. Free amino acids in sea urchin eggs and embryos. Proc. Soc. exp. Biol, and Med. 75, 30–32.Google Scholar
  13. BERG, W.E., 1965. Rates of protein synthesis in whole and half embryos of the sea urchin. Exp. Cell Res. 40, 469–489.PubMedGoogle Scholar
  14. BERNHARD, M., 1957. Die Kultur von Seeigellarven (Arbacia lixula L.) in künstlichem und natürlichen Meerwasser mit Hilfe von Ionenaus-tauschsubstanzen und Komplexbildern. Pubbl. Sta. Zool. Napoli 29, 80.Google Scholar
  15. BOELL, E.J., 1955. Energy exchange and enzyme development during embryogenesis. In: Analysis of Development (B.H. Willier, P.A. Weiss und V. Hamburger, eds), pp. 520–555. Philadelphia and London: Saunders.Google Scholar
  16. BOHUS-JENSEN, A.A., 1953. The effect of trypsin on the cross fertility of sea urchin eggs. Exp. Cell Res. 5, 325–328.Google Scholar
  17. BOREI, H., 1948. Respiration of oocytes, unfertilized eggs and fertilized eggs from Psammechinus and Asterias. Biol. Bull. 95, 124–150.PubMedGoogle Scholar
  18. BOVERI, TH., 1889. Ein geschlechtlich erzeugter Organismus ohne mütterliche Eigenschaften. Sitzber. Ges. Morph. Physiol. München 5, 73–80.Google Scholar
  19. BOVERI, TH., 1895. Über die Befruchtungs- und Entwicklungsfähigkeit kernloser Seeigeleier und über die Möglichkeit ihrer Bastardierung. Wilhelm Roux’ Arch. Entwicklungsmech. Organismen 2, 394–443.Google Scholar
  20. BOVERI, TH., 1901. Die Polarität von Oocyte, Ei und Larve des Strongylocentrotus lividus. Zool. Jahrb. Anat. Ont. 14, 630–653.Google Scholar
  21. BOVERI, TH., 1918. 2 Fehlerquellen bei Merogonieversuchen und die Entwicklungsfähigkeit merogonischer und partiell-merogonischer Seeigelbastarde. Wilhelm Roux’ Arch. Entwicklungsmech. Organismen 44, 417–471.Google Scholar
  22. BRACHET, J., BIELIAVSKY, N., TENCER, R., 1962. Nouvelle observation et hypothèses sur la létalité chez les hybrides. Bull. Acad. roy. Belg. 48, 255–277.Google Scholar
  23. BRACHET, J., HULIN, N., 1970. Observations sur les acides dèsoxy-ribonucleiques des hybrides lètaux entre oursins. Exp. Cell Res. 60, 393–400.PubMedGoogle Scholar
  24. BROOKBANK, J.W., 1970. DNA synthesis and development in reciprocal interordinal hybrids of a sea urchin and a sand dollar. Develop. Biol. 21, 29–47.PubMedGoogle Scholar
  25. BROOKBANK, J.W., CUMMINS, D.E., 1972. Microspectrophotometry of nuclear DNA during the early development of a sea urchin, a sand dollar, and their interordinal hybrids. Develop. Biol. 29, 234–240.PubMedGoogle Scholar
  26. CHAFFEE, R.R., MAZIA, D., 1963. Echinochrome synthesis in hybrid sea urchin embryos. Develop. Biol. 7, 502–512.PubMedGoogle Scholar
  27. CHEN, P.S., 1958. Further studies on free amino acids and peptides in eggs and embryos of different sea urchin species and hybrids. Experientia 14, 369–371.PubMedGoogle Scholar
  28. CHEN, P.S., 1962. Trennung der freien Aminosäuren und Peptide von Seeigeleiern mittels Ionenaustauschchromatographie. Rev. Suisse Zool. 69, 288–296.Google Scholar
  29. CHEN, P.S., 1967. Biochemistry of nuclei-cytoplasmic interactions in morphogenesis. In: The Biochemistry of Animal Development (R. Weber, ed.), Vol. II, pp. 115–191. New York and London: Academic Press.Google Scholar
  30. CHEN, P.S., 1971. Biochemical Aspects of Insect Development. Basel: Karger Verlag.Google Scholar
  31. CHEN, P.S., BACHMANN-DIEM, C, 1964. Studies on the transamination reactions in the larval fat body of Drosophila melanogaster. J. Insect Physiol. 10, 819–829.Google Scholar
  32. CHEN, P.S., BALTZER, F., 1958. Species-specific differences in free amino-acids and peptides in sea urchin eggs and embryos (pure species and hybrids). Nature 181, 98–100.PubMedGoogle Scholar
  33. CHEN, P.S., BALTZER, F., 1962. Experiments concerning the incorporation of labeled adenine into ribonucleic acid in normal sea urchin embryos and in the hybrid Paracentrotus ♀ x Arbacia♂. Experientia 18, 522–524.Google Scholar
  34. CHEN, P.S., BALTZER, F., 1964. Further morphological and biochemical studies on normal and hybrid embryos of sea urchins. Experientia 20, 236–240.PubMedGoogle Scholar
  35. CHEN, P.S., BALTZER, F., ZELLER, CH., 1960. Changes in nucleic acids in early amphibian and sea urchin embryos (pure species, merogonic and hybrid combinations). In: Symposium Germ Cells and Development (S. Ranzi, ed.), pp. 506–523. Milan: Inst. Intern. Embryol. and Fondazione A. Baseli.Google Scholar
  36. CHEN, P.S., LEVENBOOK, L., 1966. Studies on the haemolymph proteins of the blowfly Phormia regina. II. Synthesis and breakdown as revealed by isotopic labeling. J. Insect Physiol. 12, 1611–1627.PubMedGoogle Scholar
  37. DENIS, S., 1968. Changes in the level of triphosphopyridine nucleotides during development of sea urchin eggs (normal and lethal hybrids). Biochim. Biophys. Acta 157, 212–214.PubMedGoogle Scholar
  38. DENIS, H., BRACHET, J., 1969a. Gene expression in interspecific hybrids. I. DNA synthesis in the lethal cross Arbacia lixula ♂ x Paracentrotus lividus ♀. Proc. Nat. Acad. Sci. 62, 194–201.Google Scholar
  39. DENIS, H., BRACHET, J., 1969b. Gene expressions in interspecific hybrids. II. RNA synthesis in the lethal cross Arbacia lixula x Paracentrotus lividus ♀. Proc. Nat. Acad. Sci. 62, 438–445.Google Scholar
  40. DENIS, H., BRACHET, J., 1970. Expression du génome chez les hybrides interspecifiques. Fidélité de la transcription dans le croisement létal Arbacia lixula x Paracentrotus lividus ♀. Eur. J. Biochem. 13, 86–93.PubMedGoogle Scholar
  41. DEUCHAR, E.M., 1961. Amino-acid activation in embryonic tissues of Xenopus laevis. I. Increased 32 p exchange between pyrophosphate and adenosine triphosphate in the presence of added 1-leucine. Exp. Cell Res. 25, 364–373.PubMedGoogle Scholar
  42. ELSTER, H.J., 1935. Experimentelle Beiträge zur Kenntnis der Physiologie der Befruchtung bei Echinoiden. Wilhelm Roux’ Arch. Entwicklungsmech. Organismen 133, 1.Google Scholar
  43. FEDECKA-BRUNNER, B., ANDERSON, M., EPEL, D., 1971. Control of enzyme synthesis in early sea urchin development. Aryl sulfatase activity in normal and hybrid embryos. Develop. Biol. 25, 655–671.Google Scholar
  44. FEDECKA-BRUNNER, B., EPEL, D., 1969. Nuclear control of “lysosomal” aryl sulfatase activity in sea urchin embryos. J. Cell Biol. 43, 35a.Google Scholar
  45. FICQ, A., BRACHET, J., 1963. Métabolisme des acides nucleiques et des protéines chez les embryos normaux et les hybrides létaux entre echinodermes. Exp. Cell Res. 32, 90–108.PubMedGoogle Scholar
  46. FLICKINGER, R.A., 1957. Evidence from sea urchin-sand dollar hybrid embryos for a nuclear control of alkaline phosphatase activity. Biol. Bull. 112, 21–27.Google Scholar
  47. GEUSKENS, M., 1968. Etude ultrastructurale des embryos normaux et des hybrides létaux entre echinodermes. Exp. Cell Res. 49, 477–487.PubMedGoogle Scholar
  48. GIUDICE, G., 1973. Developmental Biology of the Sea Urchin Embryo. New York and London: Academic Press.Google Scholar
  49. GLIŠIN, V.R., GLIŠIN, M.V., 1964. Ribonucleic acid metabolism following fertilization in sea urchin eggs. Proc. Nat. Acad. Sci. 52, 1548–1553.PubMedGoogle Scholar
  50. GRIFFITHS, M., 1965. A study of the synthesis of naphthaquinone pigments in the larvae of 2 species of sea urchins and their reciprocal hybrids. Develop. Biol. 11, 433–447.PubMedGoogle Scholar
  51. GROSS, P.R., COUSINEAU, Q.H., 1963. Synthesis of spindle associated proteins in early cleavage. J. Cell Biol. 19, 260–265.PubMedGoogle Scholar
  52. GROSS, P.R., KRAEMER, K., MALKIN, L.J., 1965. Base composition of RNA synthesized during cleavage of the sea urchin embryo. Biochem. Biophys. Res. Comm. 18, 569–575.PubMedGoogle Scholar
  53. GUSTAFSON, T., 1952. Nitrogen metabolism, enzymic activity, and mitochondrial distribution in relation to differentiation in the sea urchin egg. From the Wenner-Gren Inst. Exp. Biol., Uppsala.Google Scholar
  54. GUSTAFSON, T., 1965. Morphogenetic significance of biochemical patterns in sea urchin embryos. In: The Biochemistry of Animal Development (R. Weber, ed.), Vol. I, pp. 139–202. New York and London: Academic Press.Google Scholar
  55. GUSTAFSON, T., HASSELBERG, I., 1950. Alkaline phosphatase activity in developing sea urchin eggs. Exp. Cell Res. 1, 371–375.Google Scholar
  56. GUSTAFSON, T., HASSELBERG, I., 1951. Studies on enzymes in the developing sea urchin egg. Exp. Cell Res. 2, 642–672.Google Scholar
  57. GUSTAFSON, T., HJELTE, M.B., 1951. The amino acid metabolism of the developing sea urchin egg. Exp. Cell Res. 11, 474–490.Google Scholar
  58. GUSTAFSON, T., HÖRSTADIUS, S., 1957. Changes in the determination of the sea urchin egg induced by amino acids. Pubbl. Sta. Zool. Napoli 29, 407–424.Google Scholar
  59. GUSTAFSON, T., LENICQUE, P., 1952. Studies on mitochondria in the developing sea urchin egg. Exp. Cell Res. 3, 251–274.Google Scholar
  60. HAGSTRÖM, B.E., 1956. Studies on the fertilization of jelly-free sea urchin eggs. Exp. Cell Res. 10, 24–28.PubMedGoogle Scholar
  61. HAGSTRÖM, B.E., 1959. Experiments on hybridization of sea urchins. Arkiv Zool., Ser. 2, 12, 127–135.Google Scholar
  62. HARDING, C.V., HARDING, D., 1952a. Cross fertilization with the sperm of Arbacia lixula. Exp. Cell Res. 3, 475–484.Google Scholar
  63. HARDING, C.V., HARDING, D., 1952b. The hybridization of Echinocardium cordatum and Psammechinus miliaris. Arkiv Zool. 4, 91–93.Google Scholar
  64. HARDING, C.V., HARDING, D., PERLMANN, P., 1954. Antigens in sea urchin hybrid embryos. Exp. Cell Res. 6, 202–210.PubMedGoogle Scholar
  65. HARVEY, E.B., 1956. The American Arbacia and other sea urchins. New Jersey: Princeton University Press.Google Scholar
  66. HÖRSTADIUS, S., 1936. Studien über heterosperme Seeigelmerogone nebst Bemerkungen über einige Keimblattchimäsen. Mém. Mus. R. d’Hist. Nat. Bruxelles, sér. 2, fasc. 3, 801–880.Google Scholar
  67. HULTIN, T., 1948a. Species specificity in fertilization reaction. The role of the vistelline membrane of sea urchin eggs in species specificity. Arkiv Zool. 40A, no. 12, 1–9.Google Scholar
  68. HULTIN, T., 1948b. Species specificity in fertilization reaction. II. Influence of certain factors on the cross-fertilization capacity of Arbacia lixula (L.). Arkiv Zool. 40A, no. 20, 1–8.Google Scholar
  69. HULTIN, T., 1961. The effect of puromycin on protein metabolism and cell division in fertilized sea urchin eggs. Experientia 17, 410–411.PubMedGoogle Scholar
  70. IMMERS, J., RUNNSTRÖM, J., 1960. Release of respiratory control by 2,4-dinitrophenol in different stages of sea urchin development. Develop. Biol. 2, 90–104.PubMedGoogle Scholar
  71. KAESTNER, A., 1963. Lehrbuch der speziellen Zoologie. (Teil I. Wirbellose), pp. 1160–1299. Jena: Gustav Fischer.Google Scholar
  72. KAVANAU, J.L., 1953. Metabolism of free amino acids, peptides and proteins in early sea urchin development. J. exp. Zool. 122, 285–337.Google Scholar
  73. KAVANAU, J.L., 1954a. Amino acid metabolism in developing sea urchin embryos. Exp. Cell Res. 6, 563–566.PubMedGoogle Scholar
  74. KAVANAU, J.L., 1954b. Amino acid metabolism in the early development of the sea urchin Paracentrotus lividus. Exp. Cell Res. 7, 530–557.PubMedGoogle Scholar
  75. LINDAHL, P.E., 1939. Zur Kenntnis der Entwicklungsphysiologie des Seeigeleies. Z. vergl. Physiol. 21, 233–250.Google Scholar
  76. LOEB, J., 1904. Über Befruchtung, künstliche Parthenogenese und Cytolyse des Seeigeleies. Pflüger’s Arch. ges. Physiol. 103, 257–265.Google Scholar
  77. LUNDBLAD, G., 1949. Proteolytic activity in eggs and sperms from sea urchins. Nature 163, 643.PubMedGoogle Scholar
  78. LUNDBLAD, G., 1950. Proteolytic activity in sea urchin gametes. Exp. Cell Res. 1, 264–271.Google Scholar
  79. MARKMAN, B., 1961a. Regional differences in isotopic labeling of nucleic acid and protein in early sea urchin development. Exp. Cell Res. 23, 118–129.PubMedGoogle Scholar
  80. MARKMAN, B., 1961b. Differences in isotopic labeling of nucleic acid and protein in sea urchin embryos developing from animal and vegetal egg halves. Exp. Cell Res. 25, 224–227.PubMedGoogle Scholar
  81. MCCLUNG, C.E., 1939. Chromosome numbers in animals. Tab. Biol. 18, 34.Google Scholar
  82. MONROY, A., GROSS, P.R., 1967. The control of gene action during echinoderm embryogenesis. Exp. Biol. Med. 1, 37–51.Google Scholar
  83. MONROY, A., MAGGIO, R., 1966. Amino acid metabolism in the developing embryos. In: Physiology of Echinodermata (R.A. Boolootian, ed.), pp. 74 3–756. New York, London and Sidney: John Wiley and Sons.Google Scholar
  84. MONROY, A., MAGGIO, R., RINALDI, A.M., 1965. Experimentally induced activation of the ribosomes of the unfertilized sea urchin egg. Proc. Nat. Acad. Sci. 54, 107–111.PubMedGoogle Scholar
  85. MOOG, F., 1965. Enzyme development in relation to functional differentiation. In: The Biochemistry of Animal Development (R. Weber, ed.), Vol. I, pp. 307–365. New York and London: Academic Press.Google Scholar
  86. MOORE, A.R., 1943. Maternal and paternal inheritance in the plutei of hybrids of the sea urchins Strongylocentrotus purpuratus and Strongylocentrotus franciscanus. J. exp. Zool. 94, 211–228.Google Scholar
  87. MOORE, A.R., 1957. Biparental inheritance in an interordinal cross of sea urchin and sand dollar. J. exp. Zool. 135, 75–79.PubMedGoogle Scholar
  88. NEMER, M., 1963. Old and new RNA in the embryogenesis of the purple sea urchin. Proc. Nat. Acad. Sci. 50, 230–235.PubMedGoogle Scholar
  89. NEMER, M., BARD, S.G., 1963. Polypeptide synthesis in sea urchin embryogenesis: An examination with synthetic polyribonucleotides. Science 140, 664–666.PubMedGoogle Scholar
  90. NEMER, M., INFANTE, A.A., 1965. Messenger RNA in early sea urchin embryos: size classes. Science 150, 217–221.PubMedGoogle Scholar
  91. OZAKI, H., 1965. Differentiation of esterases in the development of echinoderms and their hybrids. Ph.D. Thesis, University of Washington. (Cited in Whiteley and Whiteley, 1972).Google Scholar
  92. OZAKI, H., WHITELEY, A.H., 1970. L-malate dehydrogenase in the development of the sea urchin Strongylocentrotus purpuratus. Develop. Biol. 21, 196–215.PubMedGoogle Scholar
  93. PAIGEN, K., 1963. Changes in inducibility of galactochinase and galactocidase during inhibition of growth in Escherichia coli. Biochem. Biophys. Acta 77, 318–328.PubMedGoogle Scholar
  94. PERLMANN, P., 1953. Soluble antigens in sea urchin gametes and developmental stages. Exp. Cell Res. 5, 394–399.PubMedGoogle Scholar
  95. PERLMANN, P., GUSTAFSON, T., 1948. Antigens in the egg and early developmental stages of the sea urchin. Experientia 40, 481–483.Google Scholar
  96. RUNNSTRöM, J., 1952. The cell surface in relation to fertilization. Symp. Soc. exp. Biol. 6, 39–88.Google Scholar
  97. RUNNSTRÖM, J., MONNE, L., BROMAN, L., 1943. On some properties of the surface layers in the sea urchin egg and their changes upon activation. Arkiv Zool. 35A, no. 3, 1–32.Google Scholar
  98. SPIEGEL, M., OZAKI, H., TYLER, A., 1965. Electrophoretic examination of soluble proteins synthesized in early sea urchin development. Biochem. Biophys. Res. Comm. 21, 135–140.PubMedGoogle Scholar
  99. SPIRIN, A.S., NEMER, M., 1965. Messenger RNA in sea urchin embryos: cytoplasmic particles. Science 150, 214–217.PubMedGoogle Scholar
  100. TAYLOR, C.V., TENNENT, D.H., 1924. Preliminary report on the development of egg fragments. Carnegie Inst. Year Book Nr. 23.Google Scholar
  101. TENNENT, D.H., 1912b. Studies in cytology I. A further study of the ters in Echinoderm hybrids. Wilhelm Roux’ Arch. Entwicklungsmech. Organismen 29, 1–14.Google Scholar
  102. TENNENT, D.H., 1912a. The behavior of the chromosomes in cross-fertilized echinoid eggs. J. Morph. 23, 17–29.Google Scholar
  103. TENNENT, D.H., 1912b. Studies in cytology I. A further study of the chromosomes of Toxopneustes variegatus. II. The behavior of the chromosomes in Arbacia-Toxopneustes crosses. J. exp. Zool. 12, 391–411.Google Scholar
  104. TENNENT, D.H., 1914. The early influence of the spermatozoan upon the characters of echinoid larvae. Carnegie Inst. Wash. 5, 127–138.Google Scholar
  105. TERMAN, S.A., GROSS, P.R., 1965. Translation-level control of protein synthesis during early development. Biochem. Biophys. Res. Comm. 21, 595–600.PubMedGoogle Scholar
  106. TYLER, A., TYLER, B.S., 1966. Physiology of fertilization and early development. In: Physiology of Echinodermata (R.S. Boolootian, ed.), pp. 683–741. New York, London and Sydney: Interscience Publishers, John Wiley and Sons.Google Scholar
  107. UBISCH, VON, L., 1953. Über Seeigelmerogone. Experientia 9, 294.Google Scholar
  108. UBISCH, VON, L., 1954. Über Seeigelmerogone. Pubbl. Sta. Zool. Napoli 25, 246–340.Google Scholar
  109. UBISCH, VON, L., 1955. Über Seeigelbastarde. Exp. Cell Res. Suppl. 3, 358–365.Google Scholar
  110. UBISCH, VON, L., 1957a. Merogone und Bastarde von Seeigeln. Nova Acta Leopoldina 19, 5–12.Google Scholar
  111. UBISCH, VON, L., 1957b. Über Seeigelmerogone II. Pubbl. Sta. Zool. Napoli 30, 279–308.Google Scholar
  112. UBISCH, VON, L., 1959. Die Entwicklung von Genocidaris maculata und Sphaerechinus granularis, sowie Bastarde und Merogone von Genocidaris. Pubbl. Sta. Zool. Napoli 31, 159–208.Google Scholar
  113. VILLIGER, M., CZIHAK, G., TARDENT, P., BALTZER, F., 1970. Feulgen microspectrophotometry of spermatozoa and blastula nuclei of different sea urchin species. Exp. Cell Res. 60, 119–126.PubMedGoogle Scholar
  114. WHITELEY, A.H., BALTZER, F., 1958. Development, respiratory rate and content of desoxyribonucleic acid in the hybrid Paracentrotus ♀ x Arbacia ♂. Pubbl. Sta. Zool. Napoli 30, 402–457.Google Scholar
  115. WHITELEY, H.R., MCCARTHY, B.J., WHITELEY, A.H., 1970. Conservatism of base sequences in RNA for early development of echinoderms. Develop. Biol. 21, 216–242.PubMedGoogle Scholar
  116. WHITELEY, A.H., WHITELEY, H.R., 1972. The replication and expression of maternal and paternal genomes in a blocked echinoid hybrid. Develop. Biol. 29, 183–198.PubMedGoogle Scholar
  117. WILDE, C.E., 1955a. The urodele neuroepithelium. I. The differentiation in vitro of the cranial neural crest. J. exp. Zool. 130, 573–596.Google Scholar
  118. WILDE, C.E., 1955b. The urodele neuroepithelium. II. The relationship between phenylalanine metabolism and the differentiation of neural crest cells. J. Morph. 97, 313–344.Google Scholar
  119. WILDE, C.E., 1956. The urodele neuroepithelium. III. The presentation of phenylalanine to the neural crest by archenteron roof mesoderm. J. exp. Zool. 133, 409–440.Google Scholar
  120. YOUNG, R.S., 1958. Development of pigment in the larvae of the sea urchin, Lytechinus variegatus. Biol. Bull. 114, 394–403.Google Scholar

Copyright information

© Springer-Verlag Berlin · Heidelberg 1975

Authors and Affiliations

  • P. S. Chen
  • F. Baltzer

There are no affiliations available

Personalised recommendations