354 Examination of the Catalogue of 



the rest of the surface, extending to the caudal fin, and 

 containing, just back of the dorsal fin, one isolated plate. 

 Subcaudal spines shorty stout, smooth, and a little in- 

 curved. Mouth large j prominent, armed with large, 

 strong teeth ; eyes large, and distant an inch and a half 

 from the mouth ; nostrils less tl^an a quarter of an inch In 

 front of eyes- The number of rays contained in the fins 

 are as follows; ., 



D. 10. P. 12. A. 10. C. 10. 



r 

 _ -\ I 



The length of this specimen, In its present dried state, 

 is fourteen inches. From the contracted and wrinkled 

 appearance of the ligamentary portion at the base of the 

 tail, it must vary considerably from the size of the living 

 fish. (Plate Vm.) 



Belonging to our cabinet, is a species of this genus, 

 presented to the Society by the Massachusetts Historical 

 Society, which corresponds pretty well with the descrip- 

 tion of the hicaudalisy but differs somewhat ; and should it 

 be decided to belong to that species, it must be consid- 

 ered a variety. In all the figures of the Ucaudalis^ I have 

 had an opportunity of examining, each hexagonal plate Is 

 represented with one or more black spots, contained within 

 the limits of the plate : the orbitar membrane exhibits 

 none of these dots. Our specimen is covered entirely 

 with disks, resembling those of some species of Asterias. 

 The centre of these disks has, in some instances, an oval 

 black spot; in others, it is wanting; but in all cases, the 

 disks are surrounded with these large, circular, deep brown 

 spots, which are probably black in the living specimen. 

 These are smaller in front of the pectoral fins, and are 

 not only continued over the entire tail, but are distributed 

 over the membrane of the orbit. 



Since this paper was read to the Society, I have seen 



