PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 579 



coast of the TJiiited States, which have been referred to it, it becomes 

 practically impossible to separate it from the genus Icelus of Kroyer. 

 Some of the different members of Ar/erfw/s are more like Icelus hmnatus 

 than they are like each other. At present we are unable to draw any 

 satisfactory dividing line among these species, and elsewhere (Syn. 

 Fish. N. A., 689) we have referred all of them to Icelus. In the same 

 memoir we have mentioned the specimens which here become the types 

 of A. fenestralis as " Northern si^ecimens," rejoresenting " a marked 

 variety" of Icelus notospilotus. 



nKSCRIPTION OF A IVEIV SPECIEiii OF VROI^OPHVI^ (UROr.OPHU8 

 ASTERIAS), FROiTI ITIAZATJL.AIV A1V1> PANAMA. 



B¥ DAVID S. JOKDAN AIVD CHARI.ES II. GILBERT. 



UROLOPHUS ASTERIAS Sp. UOV. 



Disk almost round, a little broader than long ; its length just about 

 equal to length of tail. Anterior margins of disk nearly straight, the 

 tip acute, slightly exserted, much less prominent than in U. aspidurus, 

 longer in the male specimen than in the females. Distance from eye 

 to tip of snout, about one-fourth length of disk and a little more than 

 twice interorbital width. Interorbital space somewhat concave. Byes 

 small, much smaller than the large spiracles, the diameter about half 

 the interorbital width. Width of mouth 21 in its distance from tip of 

 snout. Teeth conic and sharp in the males, blunter and somewhat 

 pavement-like in the females. jSTostrils directly in front of angles of 

 mouth ; nasal folds forming a broad continuous flap, the edges of which 

 are slightly fringed. 



Ventrals jirojecting a little beyond outline of disk. Caudal spine 

 very long, somewhat longer than snout, its insertion considerably in 

 front of middle of tail. Caudal fin moderate, the upper lobe deepest, 

 inserted opposite tip of caudal spine, the lower lobe beginning farther 

 forward, the depth of the tail with caudal fin, about half the interorbital 

 space. 



Skin above everywhere rather sparsely covered with small stellate 

 prickles, these larger and more numerous toward the median line of the 

 back and head ; wanting on the ventral fin. Males and females about 

 equally rough. Median line of back with a series of rather strong, sharp 

 recurved spines, 18 to 32 in number, extending Irom the shoulders to the 

 front of the caudal spine, these usually becoming much larger and 

 sharper backward, but the largest much smaller than the spines in U. 

 aspidunis. 



Color, light brown, without distinct markings; tail, faintly edged with 

 dusky ; lower side white. 



