NOTES ON THE EMBRYOLOGY AND LARVAL DEVELOPMENT 

 OF FIVE SPECIES OF TELEOSTEAN FISHES. 



By ALBERT KUNTZ, Ph. D., 

 St. Louis University, School of Medicine. 



Contribution from the United States Fisheries Biological Station, Beaufort, N. C. 



INTRODUCTION. 



The work of which the results are embodied in the present paper comprises observa- 

 tions on the eggs and larvae of five species of teleosts, viz, Cyprinodon variegatus, Lucania 

 parva, Kirtlandia vagrans, Gobiosoma bosci, and Ctenogobius stigmaticus. This work 

 was carried on at the Beaufort, N. C, station of the Tjnited States Bureau of Fisheries 

 during the summer of 1914. It was undertaken in pursuance of a general plan of the 

 Bureau to secure a record as complete as possible of the time of spawning and of the 

 embryological and lars^al development of fishes common in these waters. 



It is not the purpose of this paper to discuss at length the embryological development 

 of each species, but rather by means of illustrations and descriptions to afford a ready 

 means of identifying eggs or lar\'al fishes at any time during embryological and larval 

 life. The eggs of the three species first named above are very typical. The study 

 of their development adds nothing essentially new to our knowledge of the embryology 

 of teleosts. The eggs of Gobiosoma bosci are characterized by a small yolk sphere and a 

 relatively large amount of protoplasm. This condition is emphasized still further 

 in the eggs of Ctenogobius stigmaticus in which the yolk sphere is exceedingly minute 

 and the quantity of protoplasm relatively enormous. The disparity of yolk in proportion 

 to the quantity of protoplasm present in these eggs leads to some interesting deviations, 

 during the process of gastrulation and the differentiation of the embryo, from the course 

 followed by the more typical teleostean eggs. 



Observations were made exclusively on living material. The eggs of each species 

 were fertilized and hatched in the laboratory. Males ripe for stripping were rarely 

 taken. In nearly all cases fertilization followed the maceration of the testes of the male 

 in the water into which the eggs were stripped. 



CYPRINODON VARIEGATUS. SHEEPSHEAD MINNOW. 



Spawning. — The spawning season of this species, which is very abundant in the 

 brackish waters of North Carolina, continues throughout the summer. According to 

 records kept by Mr. S. F. Hildebrand, director of the station, gravid females were taken 

 in Mullet Pond as early as April 17. The ovaries of these females contained, in addition 

 to the mature ova, immature ova of at least two different stages of development, thus 

 suggesting the probability that more than one brood is produced during the season. 



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