20 CALIFORNIA ACADEMY OF SCIENCES 



One specimen taken, a male, with undeveloi^ed claspers which do not nearly 

 reach the edge of ventrals. 



Family SILURID^. 



28. Felichthys panamensis (Gill). 



Abundant. Of the six specimens j)reserved, three are males and three 

 females, all being of nearly equal size. The specimens do not differ according to sex 

 in the shape of the dorsal buckler as extensively as is indicated in Steindachner's 

 figures (1876 b, Plate II). Furthermore, such difference as exists is in the opposite 

 direction to that observed by him, as the buckler is larger and proportionally 

 somewhat wider in the females than in the males. More obvious sexual differences 

 are found in the length of the ventral fins and in the shape of the anal. In females, 

 the ventrals are long, constantly extending beyond the front of the anal. In males, 

 they fail to reach the front of the anal fin. In females, the anterior portion of the 

 anal fin is produced, forming a projecting lobe, thus giving a strongly concave arch 

 to the jJosterior half of the margin of the fin. In males, there is no lobe, and the 

 margin of the fin is nearly or wholly straight. This difference in the shape of the 

 anal was noticed by Steindachner (1876 b, p. 15), but was supposed by him to be due 

 to age and not to sex. Another sexual difference seems to exist in the size of the 

 head, which in the present specimens is less in the case of the females, 34 to 3| 

 (3| in males). The specimens taken range from 325 to 360 mm. in length. 



29. Felichthys pinnimaculatus {Steindachner). 



Negro encuero. 



One of the most abundant food-fishes of the Panama market. Sexual jieculi- 

 arities seem much less strongly marked than in F. panamensis. 



30. Galeichthys lentiginosus {Eigenmann & Eigenmann). 



Frequently seen; nine specimens preserved. 



The species is at once recognized by the very long narrow occipital process, 

 by the depressed head, which is wide posteriorly and tapers rapidly forward to the 

 narrow pointed snout, by the very convex mouth, and the usually smooth head. In 

 the latter respect, however, there is much variation. The granulations may be confined 

 to the occipital process and the posterior part of occiput, and be faintly visible 

 where present, or they may entirely cover the crown forward to the interorbital 

 space. In the latter case, the pattern of sculpture is exactly similar to that figured 

 for Netuma planiceps (Steindachner, 1876 b, Plate IV), except that the granulations 

 are less definitely in series, and that an evident groove extends backward from 

 fontanel to near base of occipital process. The difference in roughness of the head 

 is dependent neither on age nor sex. The specimen with best marked granulations 

 is a female. 



