460 
Proceedings of the Royal Society 
ASCID1 ADiE. 
I 
Branchial aperture 
eight-lobed. 
Viscera on right side. 
Stigmata curved. 
Corella. 
Viscera on left side. 
Stigmata straight. 
Branchial aper- 
ture more than 
eight-lobed. 
Abyssascidict. 
A. wyvillii. 
C. japonica. 
Viscera extending 
beyond branchial 
sac posteriorly. 
Dorsal lamina 
in the form of 
languets. 
Ciona. 
Viscera of same length 
as branchial sac. 
Dorsal lamina in the 
form of a membrane. 
Ascidia. 
C. flemingi. 
Test normal. 
Tentacles crowded, 
not long and short 
alternately. 
Tentacles long and 
short alternately. 
Test very thick and 
solid. 
Pachychlcena 
(sub-gen.). 
Branchial sac plicated. 
Mantle forming a 
crest between tubes. 
A . pyriformis. 
Branchial sac not 
plicated. No 
crest on mantle. 
A. falcigera. 
1 
dark-col- 
Test li< 
oured. Ten- 
tacles long and 
short alter- 
nately. Dor- 
sal lamina pec- 
tinated. 
oured. Ten- 
tacles not long 
and short 
alternately. 
Dorsal lamina 
not pectinated. 
P. gig antea. 
Tentacles, Tentacles, 60 
30-35. long and 60 
very short. 
I I 
P. obesa. \ 
P. oblonga. 
Branchial sac not plicated. 
A. tenera. 
Small intermediate papilla) 
olfactory tubercle normal. 
Branchial sac plicated. 
No intermediate papillre ; 
olfactory tubercle serpentiform. 
A. translucidg. 
Test light-coloured. Test indigo-coloured, 
_J I 
; A. nigra. 
Tentacles 60. Tentacles 
A. meridional^. A. mentula. 
