CORRELATIONS OF WEIGHT. LENGTH, AND OTHER BODY 

 MEASUREMENTS IN THE WEAKFISH, CYNOSCION REGALIS. 



By WILLIAM J. CROZIER and SELIG HECHT, 



College of the City of New York. 



J* 



INTRODUCTION. 



During July and August, 1912, an opportunity was afforded at the United States 

 Fisheries Laboratory, Beaufort, N. C, to make some studies on the correlation of exter- 

 nal characters in the squeteague; the results are contained in the present paper." 



The weakfish, or squeteague {Cynoscion rcgalis) is common in Beaufort Harbor, and 

 during July and August was taken almost every day from the pound net operated by the 

 laboratory, in quantities up to 300. By far the greatest number of these fish were about 

 31 cm. long. The specimens used were therefore, to a certain degree, selected according 

 to length, with a view to having a series covering as large a range as possible. Inasmuch 

 as the squeteague is known to spawn in late spring, physiological disturbances due to 

 spawning are negligible. All the fish examined (over 400) were either "spent" or unripe; 

 so we are sure that none of the weights recorded are influenced by the ripening of the 

 gonads.* 



The material was brought from the pound in a live car and immediately removed to 

 the laboratory. Measurements were made as rapidly as possible, the time for the com- 

 plete measurement of a single fish rarely occupying more than five minutes. The possi- 

 bility of shrinkage and of loss of weight through evaporation was carefully considered. 

 To check this a number of fish were weighed and measured at 1 1 a. m. , placed in a bucket, 

 and covered (with a towel), our usual procedure, and four hours later no difference in 

 measurements could be detected. 



CORREL.^TION OF WEIGHT .\ND LENGTH. 



For the determination of the relation of weight to length, 390 fish were examined. Of 

 these 274 were females, 1 1 1 were males, and 5 were too immature for sex identification. 

 By length is meant total length, from tip of mandible of the closed mouth to the extreme 

 end of the caudal fin. This was taken by placing the fish on a board, its body perpendicu- 

 lar to and the tips of its tail just touching a raised end piece. The length was read by 

 means of a centimeter scale along the line from the mandible to the base of this end piece. 

 "Weight" means weight after the surface water and mucous have been removed with a 

 towel, and is corrected for the weight of the stomach contents. The weighing was done 

 on a platform balance sensitive to o. i gm. 



a We wish to thank Dr. J. F. Abbott, of St. Louis, for his advice in the biometrical treatment of the data; we are also indebted 

 to Dr. A. J. Goldfarb, of New York, for his suggestions during the course of the work. 



& Paton, D. Noel (Report of the Investigations on the life history of the salmon in fresh water, Fiirheries Board for Scot- 

 land, p. 1, 1S9S), for example, notes that in the European salmon, during April and May, the ovaries are 1.2 per cent and the testes 

 0.15 per cent of the total weight of the fish, whereas in November, near the spawning period, they represent 23.3 and ^.i per cent 

 of the total weight, respectively. 



19371°— vol 33—1.5 10 141 



