520 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
famil}-. On the basal or outer portion of the infundibula the stigmata 
are concentric; toward the center or apex they form a single, occasion- 
ally interrupted spiral, and are crossed and supported by some slender 
radial vessels. The surface of the sac is crossed by seven transverse 
vessels situated between the vertical rows of infundibula. Small 
imperfect or rudimentary infundibula occur along the dorsal and 
ventral edges of the sac next to the median dorsal vessel and the endo- 
style. The bars or vessels separating adjacent stigmata are slender 
and usually narrower than the stigmata, giving the infundibula an 
appearance suggesting a spider's web. 
Stomach provided with a great number of small papilla-like caeca; 
the intestinal loop narrow and comparatively little bent; anus with a 
square or somewhat two-lipped opening. 
A kidney is apparently wanting. 
The gonads have the usual positions. They are hermaphroditic 
and each consists of three or more large rounded testes arranged in a 
longitudinal row and apparently more or less fused together by their 
ventral portions but separated by clefts above (dorsally). The ovary 
appears to consist of a mass of small eggs grouped together at the 
lower (ventral) middle part of the gonad. 
There are but a few specimens of this peculiar species in the collec- 
tions, all from four localities, as follows: 
Station 333 (off S. end of Stellwagen's Bank, Race Point Light S. 18° E., 5 J 
miles, 27 fathoms, fine yeUow sand). 
Station 281 (on Stellwagen's Bank, Race Point Light S. 12° E., 8^ miles, 14 
fathoms, fine yellow sand and broken shells). 
Station 828 (north of Block Island, 15 fathoms, sand). 
Long Island Sound (no further particulars on label). 
It is evidently an inhabitant of sandy bottoms in water of moderate 
depth, and probably buries itself in the sand without becoming 
attached to any solid object. 
Note. Verrill (1879a, p. 27) lists Caesira sordida (Stimp.son), 1852, (type 
locality Charleston, S. C), among the New England ascidians, but it 
appears to have been included simply through an oversight. 
Uncertain Species. 
Caesira producta (Stimpson). 
1852. Molgida producta Stimpson, Proc. Boston Soc. Nat. Hist., vol. 4, p. 229. 
1860. Molgula producta Stimpson, Smithsonian Check-list, p. 2. 
