OF THE SHOKT SUN-FISH. 395 



Museum of the University of Edinburgh.* It measured 5 

 feet 8 inches from the snout to the tail, 3 feet 3 inches from 

 the tip of the dorsal to the tip of the anal fin, and weighed 

 489 pounds. 



On commenciug to remove the skin, which was found to 

 be rather a difficult operation, in consequence of the total 

 deficiency of any structure resembling the dermis, I found that 

 the coloured and tubercular layers of the integument were 

 attached to the external surface of a structure or tissue of a 

 very peculiar kind. This tissue extended in the form of a 

 layer, varying from one-fourth of an inch to 6 inches in 

 thickness, all over the body, head, and fins. It was thickest 

 along the median line of the back and belly, of medium thick- 

 ness along the sides, and thinnest on the surface of the fins. 

 Large and thick masses of it enveloped the bones of the cra- 

 nium, and enclosed the opercular laminaB and branchiostegous 

 rays. The soft cartilaginous bones were imbedded in such a 

 manner in its substance, that they presented the appearance 

 of nuclei in it, and resembled the first traces of the skeleton 

 in the early embryo. The most distant or peripheral elements 

 of the skeleton, the fin-rays, and certain parts of the opercu- 

 lar apparatus, were so much softer and more delicate than 

 the tissue in which they were imbedded, and so completely 

 deficient in any periosteal covering, that they could only be 

 discovered in the fresh state by their translucency. 



This peculiar tissue was separated from the muscular 

 substance in its neighbourhood by the ordinary loose 

 filamentous structure (cellular membrane). Its relation 

 to the skin was very peculiar. The tissue was inelastic, 

 tough, of a dead white appearance resembling lard, granular 

 when torn, and presented very slight traces of vascularity, 



* This specimen was found in shallow water in the Firth of Forth at 

 Culrosa, lying sluggishly on one side, hut making vigorous resistance when 

 attacked. 



