32 CALIFOKNIA ACADEMY OF SCIENCES 



spine 1 1 in head, the fin projecting beyond tip of spine and reaching | distance from axil to base of 

 ventrals. Ventrals reaching to or nearly to origin of anal. Vent midway between base of ventrals 

 and front of anal. Base of anal equaling length of pectoral spine, its margin gently concave, the 

 longest ray 2-| in head. Caudal with pointed lobes, the lower longest in the type, if in head. 



Color dark steel blue or brownish above, becoming bright silvery below; posterior |- of anal 

 white, the anterior portion black v.ith a narrow white edge; pectorals and ventrals with anterior 

 (outer) face white or slightly dusky; pectorals with inner face of upper rays black; a black blotch 

 covers all of inner face of ventrals e.xcept terminal half of inner rays; barbels blackish. 



Closely related to T. mclanopus and T. miiltiradiatus, differing from the former in the longer 

 anal fin, from the latter in the black markings on lower fins. 



The description of tlie type of 2\ nviUiradiatus {Bagrus? arioides) Kner & 

 Steindachner (1864, p. 47), indicates a species witli miicli rougher sculpturing of the 

 head, a longer fontanel groove, narrower occipital process, and more anteriorly 

 inserted adipose dorsal. 



The type is a single specimen, 280 mm. long, from Panama. 



48. Tachysurus furthii (Steindachner). 



Abundant, eighteen specimens preserved. Our specimens exhibit some 

 variation in the size of the granulations on top of head, also in the extent of the 

 granulated area, which sometimes extends as far forward on the ridges as the posterior 

 border of the eye. The groove extending backwards from fontanel is variously 

 developed. An occasional specimen shows no trace of the groove; others have it 

 developed for half the distance to the occipital process; in most cases it nearly 

 reaches the base of the latter. In the interorbital region, the fontanel dejiression 

 contains no definite groove, but at the anterior end of the depression, a short oval 

 detached portion of such groove is always present. 



The interspace between dorsals is found to be 3^ to 4 in the length, not "3 to 

 3^" as given by Eigeiimann. The sjjecies stands alone in the delicate, easily 

 ruptured skin, and the very light blue color of its upper parts. 



49. Tachysurus evermanni sp. nov. 



Plate V, Fig. 10. 



7?/7je, 252 mm.; Panama Bay; C. H. Gilbert and party, collectors; No. 0706, 

 Ichthyological Collections, L. S. Jr. U. 



Very close to 7\ furthii, from which it differs in the subequal jaws (the ujiper 

 much protruding wfurlhii), the thick, gently rounded snout (thin and subtruncate 

 in furthii) , the shorter barbels, the coarser granulations on head, the absence of a 

 depressed linear pit at anterior end of fontanel depression (this always present in 

 furthii, representing a detached anterior portion of a fontanel groove), and the much 

 wider union of gill-membranes with the isthmus. 



