CILBERT AND STAUKrt — KISIIKS OF PANAMA BAY 21 



Tlie narrow [uiiiitL'd t;iioiit, and larnc convexly ciii-vcd lUdiitli combine to 

 j;ivo the latter a considerable lateral clct't, wlien set ii lioni tlu; side. The length 

 ot the head is very constant, ol to o,V in length, when measured to margin of 

 opercular membrane. Eye 3 to 3l in its distance from tij) of snout. The upper jaw 

 protrudes beyond the lower for about three-fourths the width (jf the thick upper lip. 

 The maxillary barbels extend beyond base of pectoral spine, but not beyond its basal 

 third. Pectoral pore variable, usually minute and detected with difficulty, occa- 

 sionally an obvious slit. 



The anal fin is very long, with perfectly straight margin, the rays declining 

 regularly from the longest to the last. Five specimens have respectively 23, 24, 24, 

 24 and 25 anal rays, including rudiments. The unus is anteriorly placed, its distance 

 from base of ventrals e(iualing half its distance from front of anal fin. All but one 

 of the specimens are females, and have the inner edge of the ventrals and the upper 

 side of the inner rays covered by a thickened fold of skin. 



Light brownish in life, with blue and green reflections; the lower portion of 

 the sides coarsely punctate with brown. The fins are all dusky toward tips, the basal 

 portions dull orange yellow. Maxillary barbels blackish, the others white. The 

 specimens answer well to the description of the types. 



It is evident that the relative smoothness of the head cannot serve to distin- 

 guish the nominal genera Gakichthys and Hexanemallchthijs. The character is 

 dependent partly on variation in the granulation of the bones, partly on the amount 

 of thickening of the integument. Many species from different sections of the group 

 show similar individual variations, according to which they might be placed in one 

 or the other genus. The American species with villiform teeth and comparatively 

 narrow crescentic palatine patches will be ranged under the oldest name, Oakichthiju. 



31. Galeichthys peruvianus {Liitken). 



This rare species was not seen. Described originally from Callao, it has been 

 recorded from Panama by Steindachner and by Gilbert, and from Altata, Mexico, 

 by Steindachner. It has not been procured by any of the numerous investigators 

 in northern Mexico. 



32. Galeichthys eigenmanni, sp. no v. 



Platk IV, Fig. 7. 



This species, found in al)un(lance at Panama, and identilied with (r. seemamu 

 by Eigenmann and others, seems to be an undescribed species. G. seemnnni is from 

 some unknown locality in Central America, not impr()l)ably from the Atlantic side. 

 It is described (Giinther, 1S04 r/, p. 147) as having the top of the head finel;/ 

 granular; the occipital process with a prominent ridge; vomerine patches of teeth 

 ividely separated; and particularly as having the fontanel reaching to the base of the 

 occipital process. Dr. Jordan (1883, p. 282) has re-examined the type in the 

 P>ritish Museum for this last character, and has found it as described. In all these 

 res|)ects the Panama specimens differ strongly, as shown below. 



'- Meircb 3, 190;). 



ID 



