Mshes. 



107 



and broad, wreathed as a cable, and thickly set on each ridge with 

 minute sharp spines, which point towards the tail, and are bifurcate 

 at their extremities. The upper pectoral fin is 9 lines in length, and 

 rounded. The ventral fin is united to the anal, the union being mark- 

 ed by an indenture in the membrane : the latter passes under the tail 

 in the same manner as the dorsal, and its rays are armed in the same 

 way. The ventral fin is six-rayed. The tail is short, free and round- 

 ed, its rays are divided at about a third of their length, and then sub- 

 divided, each terminating in eight delicate rays, which are rough like 



Details of Muller's Top-knot. n. Portion of the undei- side, showing the termination of the dorsal 



and anal fins beneath the caudal. />. One of the fin-rays magnified c. Spines of fin-ray. <f. Upper 

 pectoral fin, natural size. c Lower pectoial fin, natural size. 



the others. The mouth is nearly vertical, forming an angle of about 

 9 or 10 degrees. Mr. Yarrell observes that it is small, but in my spe- 

 cimen it is capable of being extended to one inch by three quarters : 

 the teeth are small, and numerous in both jaws, with a cluster of small 

 ones on the vomer : when the mouth is extended the membranes are 

 particularly transparent. The branchiostegous membrane is also re- 

 markably clear; rays 3 + 4. The whole of the upper surface, includ- 

 ing the eye-lids, cheeks and body, is rough, being covered with small 

 scales, denticulated on their edges, which appear to be turned up : 

 the head is rougher than the body. The upper eye is larger than the 

 under one. The lateral line rises over the upper angle of the opercu- 



