116 Dr. Johnston on Scottish MoUusca. 



Hub. Amongst corallines in deep water. Coast of Berwickshire, not un- 

 common. 



Desc. Body oblong, tapered behind, one inch in length, 

 three or four lines broad, grey, marked with brown and freck- 

 led much in the same way as the common slug ; the back flat, 

 obscurely tuberculated ; the sides abrupt. Mouth overhung 

 with a semicircular veil, the margin of which is cut into seven 

 tentacular processes, of which the lateral ones are the longest. 

 Tent (tenia exertile from wide entire circular sheaths, columnar, 

 white, the apex yellowish and cleft into narrow pinnatifid seg- 

 ments. BraneMce arborescent, small and not much divided, 

 separate, the tufts five or six on each side, the first and last 

 pairs minute. Foot white, oblong, plain. 



The Tritonia pulcra described in Edin. New Phil. Journ. v. 

 p. 78. is probably a variety of this, distinguished by the red 

 colour of the body, which is marked across the back with three 

 narrow whitish bands, and speckled with minute ocellated 

 dots. I have never met with a specimen but the one from 

 which the original description was taken, and further expe- 

 rience has taught me that colour is far from constant in these 

 animals. I have seen specimens of T. plebeia of a whitish co- 

 lour, either uniform or marked with spots of milk-white opa- 

 city. 



3. Melibea*, Rang, 



Character. Animal limaciform, the mouth overhung 

 with a veil: tentacula two, dorsal, filiform, retractile within 

 wide sheaths : branchice in separate muricated or tuberculated 

 masses placed in a single row along each margin of the back : 

 foot linear-oblong, tapered posteriorly, plane : vents as in Tri- 

 tonia. 



1. M. pinnatifida, branchial masses in eight or nine pairs. 



Tritonia pinnatifida, Cuv. Reg. Anim. iii. 53. note. Fleming in Edin. 



Encyclop. xiv. 619. Flem. Brit. Anim. 284. Johnston in Mag. Nat. 



Hist. viii. 61. fig. 4. — Doris pinnatifida, Montagu in Linn. Trans, vii. 



78. pi. 7. fig. 2, 3. Tnrt. Brit. Faun. 134. Penn. Brit. Zool. iv. 83. 



edit. 1812. 

 Hah. In deep water amongst corallines. Coast of Berwickshire. 



• Melibcp.a is the name of a maritime town of Thessaly, famous for its 

 purple dye, and undoubtedly is the original of Rang's name for this genus. 



