of Simple Ascidians. 363 
Corella larveeformis, Hancock. 
Branchial sac with inconspicnous ae at the intersections 
base to the branchial aperture & of an inch, and to the anal 
aperture 14 inch. 
.. We are indebted to Mr. A. G. More for the knowledge of 
this interesting and very distinct species. Two specimens 
were obtained at Roundstone, Connemara, in 1869. 
` C. larveformis is distinguished at once from C. parallelo- 
gramma by the extraordinary elongation of the anal tube, and 
the comparative deficiency ‘of colour, though much reliance 
cannot be placed on this fida: as the specimens had been 
some time in spirit before they came into our possession. The 
fewness of the rows of branchial spirals, and the consequent 
comparative largeness of the spirals themselves, also distin- 
guish this species. 
Corella ovata, Hancock. 
Body ovate, widest above, not much compressed, adhering 
by the base, where there are a few root-like processes. Aper- 
tures very little produced, almost sessile; the branchial one 
terminal, the anal placed at a little distance down the ventral 
margin. Test soft, smooth, delicate, and perfectly transparent, 
revealing the colours and structure of the enclosed mantle an 
viscera, Mantle thin, transparent, of a buff flesh-colour, some- 
cles few and delicate, of a reddish colour. Branchial sac with 
. thin, delicate papille, very slightly produced ; the spirals com- 
