80 BRITISH TUXICATA. 



Externally the test was continuous without depression 

 or indication of any kind that it covered more than one 

 individual, excepting that it had four orifices instead 

 of two ; internally there was a ridge dividing it into 

 two cavities, which however were not closed, but com- 

 municated freely with each other. 



3. Ascidia robusta Hancock. 

 (PL XX, figs. 2 and 3 ; and fig. 15 in text.) 



[Ascidia ml) list a HANCOCK in Ann. Nat. Hist. (4), VI (1870), 



p. 358.] 



Body elongated, irregularly ovate, produced in front, 

 very coarse, with a tinge of red, particularly towards 

 the orifices ; adhering by the whole side, but sometimes 

 much distorted and with adherent, root-like prolonga- 

 tions. Apertures tubular, much produced, the branchial 

 one terminal, the anal more than half way down, and 

 inclined backwards ; ocelli red. Test extremely thick, 



e 



tough, hard, and cartilaginous, usually with root-like 

 prolongations, semi-transparent, very coarse and rough, 

 irregularly furrowed and pitted, and frequently much 

 overgrown with zoophytes. Mantle tinged with red, 

 intensified towards the orifices ; tubes long, the anal 

 one much produced and turned backwards. Tt>itf<iai/<i r 

 filament* rather slender, not crowded, with small ones 

 between the larger. Branchial xac extending a little 

 behind the visceral mass ; minutely plicated with well- 

 developed tubercles, alternately large and small. Oral 

 bimina ribbed transversely and. strongly pectinated 

 near the mouth. 



Leiti'/tlt from four to five inches. 



Huh. Between the roots of Laminaria ditjitata. 



CHANNEL ISLANDS. [Herm,] Guernsey (Norman). 

 First record. Hancock, 1870; coll. Norman [18(35]. 



This is not only one of the largest, but is perhaps 

 the coarsest, of the British Tunicata. The test (fig. 

 15) is usually more or less tinged with red, principally 



