324 H. H. NEWMAN. 



5. After watching the spawning of this -species in the open, I 

 believe that large males, when at the height of their sexual 

 period, control considerable areas in the Eel Pond and elsewhere. 

 Although an active male may pursue a female or another male 

 for considerable distances he soon returns to the neighborhood 

 over which he seems to exercise authority. This phenomenon 

 is by no means unusual in fish. 



Sc. vital Dimorphism. 



The following passages, refering to sexual dimorphism, are 

 selected from Jordan and Evermann's systematic account : 



"... fins moderate, the dorsal inserted in males midway between 

 snout and tip of caudal ; in females farther back ; oviduct attached to 

 anterior ray of anal fin for one-half to two-thirds its length ; . . . Colora- 

 tion in males dark dull green, the belly more or less orange yellow ; sides 

 with numerous quite narrow, ill-defined silvery bars made up of silvery 

 spots, most distinct posteriorly ; besides these are numerous conspicuous 

 white or yellow spots, irregularly scattered ; vertical fins dark with numer- 

 ous small round pale spots ; dorsal often with a blackish spot on its last 

 ray ; anal and ventrals yellow antertiorly ; under side of head yellow ; 

 young males with alternate bars of dark and silvery, the former becoming 

 in time the ground color, the dorsal ocellus more distinct. Females nearly 

 plain olivaceous, lighter below, without spots or bars, the scales finely 

 punctate ; sides often with about fifteen dark crossbars or shades. Young, 

 especially young females, with more or less distinct dark cross bands ; these 

 always present in the very young, in females narrower than the interspaces, 

 in males much broader and less numerous." 



This description, while accurate enough so far as it goes, needs 

 to be supplemented with regard to certain details. It also fails to 

 take into consideration the fact that there are marked seasonal 

 changes not only in color but in the actual size of certain parts 

 such as belly and fins, and in the production of certain tempor- 

 ary organs in the male. 



First of all I would like to supplement Jordan and Evermann's 

 account and to call attention to certain points. Then I shall be 

 in a position to discuss the seasonal changes. 



The description of the male is fairly accurate for one out of the 

 breeding season. I wish, however, to call attention to the rel- 

 atively large size of the dorsal and anal fins of the male as com- 

 pared with those of the female (see Plate XXVII., Figs. I and 2). 



