POLTZOA. 97 



mouth with from five to seven spines ; lower lip straight, entire ; ovicell 

 globose, surface granular. 



Britain. Mediterranean. America. Australia. 



* 49. L. lyallii, BusJc, I.e., p. 75. Cells oval, walls thin, verrucose, 

 or rugose ; mouth raised, margin thickened, with a spout-like sinus in 

 front, and five to six spines on the sides and above ; a small vibraculum 

 on many of the cells, on one side near the top. {Busk.) 



New Zealand (Lyall). On Fuci. 



3. Without Avicularia or Vibracula. 



A. WITH ORAL SPINES. 



50. L. VariolOSa, Busk, I.e., p. 75 ; Johnston, I.e., p. 317. Cells 

 oval, immersed or sub-immersed, usually disposed in linear series; 

 punctured or areolated round the margin, granular (sometimes punc- 

 tured) in front ; mouth rounded or sub-quadrangular, with two to four 

 close set spines quite at the summit ; lower lip with a projecting mucro 

 and an internal bifid denticle ; ovicells deeply immersed, also areolated 

 round the margin. 



Lyall's Bay. Britain. 



51. L. nitida, Busk, I.e., p. 76 ; Johnston, I.e., p. 319. Cells ovate, 

 raised in front ; wall composed of four to nine ribs on each side, the 

 spaces between which are filled up by a diaphanous membrane ; mouth 

 with four to six oral spines ; ovicell sub-globose, surface granular. 



Britain. 



52. L. ventriCOSa, Hassall; Busk, I.e., p. 78 ; Johnston, I.e., p. 

 305. Cells distinct above, or raised, immersed at the base, ventricose, 

 ovate or sub-globose; mouth sub-orbicular, with a thickened raised 

 margin ; a bifid denticle on the lower lip, and four (rarely more) 

 marginal spines ; surface granular or irregularly striated ; usually a 

 pointed or broad mucro in front of the mouth ; ovicells globular, 

 prominent. 



Lyall's Bay. Britain. 



53. L. urCGOlata, sp. nov. Cells large ('04 inch), ovate, ventri- 

 cose, immersed behind ; surface finely granular without any pores ; 

 mouth simple, scarcely thickened, sub-orbicular, lower lip straight ; 

 from four to seven spines on the upper margin. 



On dead shells. 



54. L. cancer, sp. nov. Cells ovate, sub-immersed, separated by 

 depressed lines ; surface coarsely granular ; lower lip produced into a 

 mucrouate hollowed process, which covers the mouth, and is trans- 

 versely striated ; a short blunt incurved spine on each side of the 

 mouth ; in the fertile cells the lower lip is not mucronate but rounded, 

 and the spines are absent ; ovicells globose, coarsely granular. 



Lyall's Bay. On Fuci. 



55. L. pellucida, sp. nov. Cells ovato-ventricose, smooth, thin, 

 translucent, a pore in the centre ; mouth nearly terminal, oblong, 

 transverse, with four or five long spines on its upper margin ; ovicell 

 (?). On Fuci. 



13 



