GEN. RHOMBUS. THE WHIFF. 239 



of those next to it, and the tail is rather long, the 

 sides approaching to parallel. 



This fish is accounted still rarer than the preced- 

 ing, although Dr. Fleming, who obtained a speci- 

 men in Zetland in 1810, was informed by the fisher- 

 men that it is not uncommon in that quarter. Mr. 

 Jenyns informs us that a specimen was obtained by 

 Professor Henslow at Weymouth, and is now in the 

 Museum of the Cambridge Philosophical Society. 

 A third has been caught on the coast of Ireland. 



The most singular feature in this species is the 

 elongation of the first dorsal ray, which is referred 

 to in the English name. In the figure of R. unima- 

 culatus of Risso, which Mr. Yarrell considers iden- 

 tical with this, and also in the figure given in 

 Fleming's Philosophy of Zoology, this appendage is 

 wanting, which leads to the conjecture that it may 

 possibly be a sexual distinction. 



(Sp. 180.) P. megastoma. The Whiff. Tlie two 

 species which yet remain to be noticed in order to 

 complete the list of those referred to this genus, differ 

 so much from the typical rhombi, that it would per- 

 haps be proper to include them in a sub-genus by 

 themselves. But for the colour being on the left 

 side, and that is a variable character, an observer 

 would be almost as ready to consider them Soles 

 as belonging to the Turbot group. The body is ob- 

 long and very narrow compared to the length, sud- 

 denly contracted before the tail, and so thin as to 

 be somewhat transparent. The membrane connect- 

 ing the fin rays is extremely delicate, and usually 



