10 



MARINE POLYZOA. 



elliptical, sublateral. Surface in front covered with minute acu- 

 minate papillae. 



Catenicella formosa, Busk, Voy. of Rattlesn. i. 360. 

 Hab. Swan Island, Banks' Strait. 



Colour light plumbeous. Parasitic upon C. margaritacea. The 

 cells are the largest of any in the vittate division, and very regu- 

 lar and uniform in size and outline. The more distinctive cha- 

 racters are taken from the comparatively broad vittse, and the flat 

 or cupped upper surface of the avicularia, which are usually con- 

 tinued downwards into a prominent ridge or ala. 



10. CATENICELLA PERFORATA. PI. VIII. figs. 1, 2. 



Cells elongated oval. Avicularian processes large, perforated 

 at the base or by several openings. Vittse long, wider below, 

 lateral. Surface in front papillose. 



Hab. New Zealand, Hooker, Lyall, Darwin. Tasmania, Hooker. 



11. CATENICELLA RINGENS. PL VIII. figs. 3, 4. 



Cells ovoid or subglobular. Avicularia usually very unequal, 

 the larger one gaping. Vittse, anterior, broad. Surface in front 

 smooth. 



Hab. New Zealand, Dieffenbach. Algoa Bay. 



Differs from C. elegans, with some forms of which it might be 

 confounded, in the absence of acuminate papillae on the anterior 

 surface, and in the comparatively greater size and peculiar gaping 

 aspect of the avicularia, or not unfrequently of one of them. 



12. CATENICELLA ELEGANS. PI. IX. 



Cells elongated, ovoid. Avicularia large and projecting, with- 

 out any superior appendage. Vittae narrow, sublateral. Surface 

 in front papillose. 



? Eucratea Contei, Audouin, Expl. i. 242 ; Savig. Eg. pi. 13. f. 1. 

 Catenicella Savignyi?, Blainv. Man. d'Act. 462. pi. 78. f. 1. 

 Catenicella elegans, Busk, Voy. of Rattlesn. i. 361. t. 1. f. 2. 

 Hab. Bass' Strait, 47 fathoms; Port Cooper, Banks' Penin- 

 sula; Algoa Bay; Port Dalrymple. 



A delicate and beautiful parasitic species ; the branches slen- 

 der and spreading; colour white and very transparent; cells 

 regular, and uniform in size and shape. There appears to be 

 little or no difference between the Australian and South African 

 species ; in the latter, however, the vittae are usually much longer, 

 extending upwards as high as the mouth. 



