NO. 2011. FISHES FROM JAPAN— JORDAN AND THOMPSON. 71 



of the Other. Their material seems to bear out this conclusion, for 

 both sexes are represented in both forms. Mr. Regan and later 

 Snyder have concluded that daimio is the male and elapoides the 

 female. This seems, however, not to be the fact. Of 18 specimens 

 before us, typical of Pterogohius daimio, 11 are females, and 7 are 

 males. In these portions only of the gonads remain, corroborating 

 the fin characters, given below, in each case. Microscopic examina- 

 tion was necessary to decide the sex. None of these have a bar 

 across the base of the caudal, as is typical of P. elapoides Giinther. 

 The male has a much more elongated spinous dorsal than the female, 

 and longer soft dorsal rays, as well as darker vertical and ventral fins. 

 The anal is narrowly edged with white. The differences between the 

 nominal species P. daimio and P. elapoides seem to be the presence 

 in the latter of an additional bar across the caudal base, vertical 

 body bands, broader in specimens of the same size. The last-named 

 characters intergrade. 



Since the original description of Pterogohius daimio by Jordan and 

 Snyder, Regan ^ has expressed the opinion that the brightly colored 

 P. daimio is the male of P. elapoides, the other alleged characters 

 entirely intergrading. Snyder ^ admits that the two species repre- 

 sent each a distinct sex but fails to find that the characters intergrade, 

 and says further that "in our collecting the sexes were not found 

 together, and the male specimens (daimio) far outnumber the females 

 (elapoides)." Among the cotypes of P. daimio Jordan and Snyder, 

 7 are females with unripe ovaries, 1 a male, while 1 eviscerated is 

 apparently a female, judging by the height of the dorsal fin. It is 

 evident, however, that the sexes are both present in each form, and 

 that they are apparently not of like distribution, P. elapoides ranging 

 farther north. At the same time some characters intergrade, as is 

 evident in the specimen from Yawatahama, and for the present we 

 may regard the question as to whether Pterogohius daimio is a distinct 

 species as still unsettled. The probabilities are that it is the northern 

 type or subspecies, although the two meet at Misaki. 



The table of measurements show that the dorsals of P. daimio are 

 much higher than in P. elapoides, the dorsals in the female being 

 higher than those in the male in the latter form. 



The head in both forms forms 0.27 to 0.29 of body length. The 

 spinous dorsal in the male daimio is 0.37 and 0.42 in two examples; 

 in the female of daimio 0.25, 0.26, 0.26, 0.28, 0.29 in five examples. 

 In the male of elapoides it is 0.25, 0.25, 0.25 in three examples; in the 

 female 0.18, 0.21, 0.22 in three. The soft dorsal in the male daimio 

 averages 0.18; in the female 12; in male elapoides 0.13; in the female 

 0.115. The fin rays and body measurements do not differ. The 



1 Aimals and Magazine of Natural History, ser. 7, vol. 15, January, 1905, p. 22. 

 i Proe. U. S. Nat. Mus., vol. 42, 1912, p. 443. 



