20 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



from which it is distinguished generically by the obsolete eyes, and spe- 

 cifically by the characters given in the following description : 



Body elongate, posteriorly much compressed, not much depressed 

 anteriorly. Head depressed, with the cleft of the mouth nearly hori- 

 zontal and one-half the length of the head, the maxillary reaching a 

 vertical line drown across the probable position of the eye. Eyes invis- 

 ible, covered by the skin; snout rounded; the jaws equal, or very 

 nearly so, the lower jaw in a preserved specimen seeming to be very 

 slightly produced. Both nostrils are provided with a flap. 



A narrow band of villiform teeth in each jaw. The gill-membrane is 

 united to the isthmus, and the branchial cleft is equal in length to the 

 distance between the first and second dorsal fins, or one-tenth of the 

 length (from snout to base of caudal). 



A groove has its origin immediately in advance of first dorsal and 

 extends medially nearly to tip of SDOut. 



The first dorsal fin is composed of two flexible spines, and is equidis- 

 tant between the snout and the base of the caudal fin ; the insertion of 

 the second dorsal is not much in advance of vent, while the insertion of 

 the anal is opposite the fifth ray of the soft dorsal; the last rays of the 

 posterior dorsal are slightly longer than its anterior one, and the fin 

 terminates opposite the anal, which is similar to the soft dorsal. A 

 very small anal papilla may be seen. 



Vertical fins low; caudal small, pointed; ventrals forming a disk, 

 which is not adherent to the belly ; pectorals like the caudal in form, 

 their free tips extending beyond the ventrals, though not approximating 

 the first dorsal, and very remote from the vent. 



Body entirely smooth, wholly free from scales, tubercles, or asperities 

 of any kind. 



The type specimen has been presented to the National Museum, where 

 it is numbered 27466. 



This species is doubtless the type of a distinct genus, which may be 

 called Othonops {rhU'^r^, veil ; w^S eye). This genus is distinguished from 

 CrystallogoMus by the concealed eyes, these organs being large and 

 .conspicuous in C. nihsoni, and possibly also by the absence of the sexual 

 difterenct's in dentition, so marked in CrystallogoMus, the male of C. 

 nilssoni being provided with strong canines. The remaining genera of 

 Gohiiiue have five or more dorsal spines, except BenthopMlus, which, with 

 three dorsal spines, has the skin verrucose. 



Since the above was in type three more specimens have been obtained 

 at the same locality, the measurements of the largest of which are 

 included in the table below. 



On examination of this specimen, 2f inches in length, I find further 

 characteristics. 



In this example, the fins are better preserved and show their normal 

 form, the caudal and pectoral being rounded, the pointed appearance 

 of those fins on the type specimen probably having been caused by 



