32 CAIJFOUNIA Al^ADKMY OF SCIENCES 



spine I J in head, tin- tin projeclinji iH-yonil lip uf spiiu- and rtMciiini; 'i distance from axil to base of 

 vcntrals. N'entrals reaching to or nearly to orij^in of anal. \'ent midway between base of ventrals 

 and front of anal. Base of anal equalinjj lcn).;th of pectoral spine, its marijin (.jently concave, the 

 longest ray 2| in head. Caudal with jxiinted lobes, the lower lunyest in the type, i j in head. 



Q)lor dark steel blue or brownish above, becoming bright silvery below; posterior | of anal 

 white, the anterior jiortion black with a narrow white edge; pectorals and ventrals with anterior 

 (outer) face wliite or slightly dusky; |)ectorals with inner face of U|)|)er rays l)lack; a blark blutch 

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



Closely relale-d to 7\ mclanopus and T. multiradifitus, difTering from the formn in tlu longer 

 anal tin, from the latter in the black markings on lower tins. 



The (le.-<cri|)tion of the type of T. muUiradinfHt^ {Bagrua? arinidex) Kner tt 

 Steintlacliiior (1864, ji. 17), iinrK-ate.s a species with miic-li loiighci- stMilptiiriiig of the 

 liead, a longer fontanel ,i;'i-0()ve, iiaiTOwer occipital process, ;iii(l innrc anteriorly 

 inserted adipose dor,sal. 



Tiie type is a single specimen, 2S() niiii. long, froiu I'anaiiia. 



48. Tachysurus furthii (Sli-i iiddchner). 



Abundant, eighteen S2)ecimens 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 mo.st cases it nearly 

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

 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 o^ to i in the length, not "3 to 

 3^" as given by Eigenmann. Tiie species stands alone in tlie delicate, easily 

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



49. Tachysurus evermanni sp. nov. 

 Pl.\tf. V, Fio. 10. 



Type, 252 mm.; Panama Bay; C. H. Gilbert and party, collectors; No. G706, 

 Iclithvological Collections, L. S. Jr. U. 



Very close to T. furthii, from which it difiers in the subecpial jaws (the upper 

 much protruding in furthii), 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. 



