50 BRITISH TUNICATA. 



incrusting, nearly colourless, spotted with orange and 

 white from the enclosed animals (PI. LIX, fig. 8). 

 Individuals irregularly arranged in sub-longitudinal 

 systems, each with a smallish common orifice (PL LIX, 

 fig. 9). Thorax white, with a dark ruby-coloured, 

 nearly black spot in front (PI. LIX, fig. 12). Branchial 

 sac with four rows of stigmata. Abdomen yellow or 

 orange-coloured, sub-sessile (PL LIX, fig. 12). 



Hah. On the underside of stones between tide- 

 marks. [On stones at low water-mark (Cocks).] 



ENGLAND. - - [Whitley (1847) and Cullercoats,] 

 Northumb. (Alder}. [Gwyllyn-vase, Falmouth, Corn- 

 wall (Cocks). Isle of Man (Forbes).] 



First record. Forbes, 1848. 



[Various stages in the development of this species, 

 observed at Tynemouth in August, 1858, are repre- 

 sented on PL LX.] 



7. Leptoclinum Listerianum Milne Edwards. 

 (Figs. 112 and 113.) 



Polyclinum LISTER in Phil. Trans, for 1834 [CXXIV, pt. 2], 

 p. 382, pi. xii, f. 1 [3 figs.] . 



Leptoclinnm Listerianum MILNE EDWARDS Obs. Ascidies 

 comp. 1841, p. 84, [in Mem. Acad. Sci. List. France, 

 XVIII (1842), p. 300;] FORBES & HANLEY Brit. Moll. 1 

 [1848], p. 17 ; [CocKS in Rep. R. Cornw. Polyt. Soc. for 

 1849 (1850), p. 74; MERRIFIELD Nut. Hist. Brighton 

 (1860), p. 81; ANSTED & LATHAM Channel IsL (1862), 

 p. 219 ; GRUBE Insel Lussin Meeresf. (1864), pp. 30, 61]. 



[Leptoclinum Lister i BRONN Thier-Reichs, III (1861), p. 

 171.] 



Colon if (fig. 112) forming a grey, transparent, shiny 

 crust, speckled with white and black. Individuals 

 dispersed without apparent order ; the common cloacal 

 orifices rising into conical or sub-tubular eminences. 

 Branchial apertures (fig. 113) with a circle of white 

 spots. Branchial sac with four rows of stigmata. 



Hal). Investing the stems of small seaweeds. [On 



