NOTES ON THE EMBRYOLOGY AND LARVAL DEVELOPMENT 

 OF TWELVE TELEOSTEAN FISHES. 



By ALBERT KUNTZ, Ph.D., 



Si. Louis University School of Medicine, 



and 



LEWIS RADCLIFFE, 



Scientific Assistant, United States Bureau of Fisheries. 



G)ntribution from the United States Fisheries Biological Station, Woods Hole, Mass. 



INTRODUCTION. 



Adequate measures for conservation of our fishery resources and the production of 

 the maximum quantity of food with the minimum of expenditure through proper propa- 

 gation methods require as their basis a reasonably complete knowledge of the life his- 

 tories and habits of the fishes. The first step in this direction is the determination of the 

 character of the eggs and young, so that they may be recognized at any stage of develop- 

 ment. Many of our important marine food fishes — e. g., cod, haddock, hake, mackerel, 

 and haUbut — have floating eggs, which may be collected with an ordinary tow net with 

 much less effort than is required to locate and capture the spawning fish. Thus this knowl- 

 edge may serve to locate the spawning grounds and also the schools of spawning fish. The 

 immediate value of knowledge of this character has been well illustrated by Dr. Hjort, of 

 Norway. Knowing the character of cod eggs, he applied this method to the coast banks 

 off northern Norway and thereby "succeeded in finding enormous shoals of cod on 

 certain banks where no fishing was carried on, and where, as a consequence of our 

 discovery, millions of cod were afterwards taken." 



The present paper embodies the results of a study of the embryology and larval 

 development of teleostean fishes taken in the region of Woods Hole, Mass., during July 

 and August, 191 5. 



The majority of the species, especially the more important ones, common to this 

 region spawn earlier in the season. Little is known of the breeding habits of the bonito 

 (Sarda sarda), the menhaden {Brevoortiatyrannus), thc-hutt^r^sh. (Poronotus triacanthus), 

 and the hake (Urophycis chuss). Females of these species in which the eggs were nearly 

 or quite mature and males from which the milt flowed freely were taken. However, all 

 attempts at artificial fertilization failed. The eggs of the bonito and the hake were never 

 taken in the plankton. With the exception of the menhaden, butterfish, and whiting, 

 the eggs of all the species described herein were artificially fertilized and hatched in the 

 laboratory. The eggs of the whiting were artificially fertilized, but all died during 



