004 DIDEMNIINiE. 



Genus EUCCELIUM, Savigny. 



Test gelatinous, sessile, and incrusting ; systems nume- 

 rous, without central cavities or distinct circumscription. 

 Tunicaries sometimes scattered, sometimes arranged in a 

 quincunx ; branchial orifice circular, without distinct 

 rays, anal orifice very minute ; abdominal viscera pushed 

 up by the side of the thorax. 



Ex. E. hospitiolum, Savigny, pi. 135, fig. 6. Individual, 

 E. hospitiolum, fig. 6, a. 



A single species only of this genus is known, inhabiting 

 the shores of Europe. 



Genus LEPTOCLINUM, Milne-Edwards. 



Test thin, sessile, incrusting, polymorphous ; systems 

 numerous. Individuals grouped irregularly round common 

 cloacal cavities, more or less ramified; branchial orifice 

 six-lobed ; abdomen pedunculate, short, smaller than the 

 thorax. 



Ex. L. gelatinosum, M ilne-Edwards, pi. 136, fig. 1. In- 

 dividual, L. gelatinosum, fig. 1, a. 



There are six species of this genus peculiar to Britain and 

 the seas of Europe. They are variously coloured, and are 

 usually found adhering to the roots of Laminariee. 



Species of Leptoclinum. 



asperurn, Milne-Edw. Lister,ianum, Milne-Edw. 



aureum, Milne-Edw. lividum, Sav. 



clavatuin, Sav. maculosum, Milne Edxv. 



gelatinosum, Milne-Edw. punctatum, Forbes. 



