No. 9.-^1856-8.] new ceylon nudxbr&nchxata, (fee, 107 



Pterochilus viridis. Kel. 



Animal light-green. Length J inch. Tentacles 2, simple, 

 long, pointed. Head with small lateral lobes. Branchiae very- 

 numerous, closely set ; long, linear, acutely pointed. Branchiae 

 green, and spotted with darker green and grey. Foot linear. 

 Found on sea-weeds, and, owing to its colour, not easily 

 recognised. Lives for a long time in confinement. Ova 

 green. 



Fam. Elysialle. 

 Genus. Elysia, Eisso. 



Animal elliptical, depressed, with wing-like lateral expan- 

 sions ; tentacles simple, with sessile eyes behind them ; foot 

 narrow. 



Elysia grandifolia. Kel, 



Head and body light-green, white, and occasionally black 

 spotted. Head and neck naked. Tentacles 2, folded longitu- 

 dinally, on side of head ; bronzed-green, tip brown. Buccal 

 tentacles 2, small. Membranous wing-like expansion on each 

 side of body ; broad anteriorly ; acutely pointed posteriorly, 

 and united at the tail. Membrane green, edged with a black 

 and a golden yellow line. No distinct foot. Orifice on the 

 back (?). Mouth beneath. 



The whole animal gives one the idea of a large leaf ; and, 

 when moving, that of a butterfly. Found on sea-weed. Some 

 are more than 3 inches long ; greatest transverse diameter, 

 with wings expanded, inches. Distinct veins, filled with 

 fluid seen on the wings ; the heart pulsating on the centre of 

 the back. I have some doubts as to the propriety of placing 

 this interesting creature under the head of Elysia. If on further 

 investigation, it is found that it does not belong to any known 

 genera, I propose naming it Hydropsyche. 



Elysia punctata. Kel, 



Smaller than the last species ; largest specimen seen measur- 

 ing li inch. 



