ASCIDIA CEASSA. 



89 



CHANNEL ISLANDS. Jersey (DoJJ), in the collection 

 of the Rev. A. M. Norman. 



First record, Hancock, 1870; coll Dodcl [1869]. 



We have seen three specimens of this well-marked 

 species ; they were all from the same locality but had 

 been some time in spirit before they were examined ; 

 none of them showed any large area of attachment; 

 on the contrary, they all seemed to have been adherent 

 by various parts of the body to seaweeds, the remains 

 of which, including a piece of the cuticle of Liuninnna 

 digitata, being impressed into the surface of one of the 

 specimens. 



FIG. 17. Ascidia crassa. Natural size. 



The test (fig. 17) is unusually thick and hard, and 

 is irregularly and strongly wrinkled ; it is pellucid and 

 of a delicate flesh-colour. The blood -channels are 

 numerous and are frequently crimson, especially those 

 appearing at the external surface, which have their 

 extremities considerably enlarged and irregularly 

 rounded or pyriform ; those observed at the inner 

 surface have the ultimate twigs slightly swollen and 

 fusiform. The enlarged crimson ones at the exterior 

 are not very plentiful and are mostly confined to the 

 vicinity of the apertures. 



The mantle is well supplied with thick interwoven 

 muscular fibres, and varies in colour from a pale rosy 

 hue to crimson, the colour being intensified towards 



