Ceylon Nadibrancliiate Molluscs, and Zoophytes. Ill 



occupies the whole of the under part of mantle. Anus opens 

 on the under surface of the posterior part of mantle. Orifice 

 of the organs of generation on the right side. 



Found on rocks in the Inner Harbour. I have scarcely 

 an}* doubt, that this is the Onchidore described by Blainville 

 from a specimen seen in the British Museum, whose habitat 

 was not known. 



The colour of the animal is of a light grey, mottled with 

 black spots in some specimens. In spirits the filamentous 

 granules are not seen, but when the animal is alive they are 

 so distinctly s and the contractile character of the filaments 

 are very observable, especially of the larger ones. 



Trevelyana, n. g. 



Body without a cloak. Two dorsal tentacles without 

 sheaths, non-retractile. Mouth in front of head, without 

 tentacles. Branchiae in a circular disc on the back ; non-re- 

 tractile. 



Trevelyana Zeylanica. Kel. 



Body 1| inch long, narrow, elevated and inflated near the 

 branchial plumes ; semi-gelatinous, white and spotted with 

 small dark orange red spots, set wide apart from each other. 

 Head rather produced and rounded ; also spotted red. Mouth 

 circular, small ; situated in front, without veil or tentacles. 

 Branchial plumes 15 or 16, situated on posterior third of 

 body, round a large disc, in the centre of which is the vent. 

 Plumes long, downy, closely set ; pure white, with a longi- 

 tudinal bright red streak on the back of each; slightly con- 

 tractile, but they do not retract into a cavity ; when extended, 

 they resemble a small tuft of marabout feathers. Genital 



