342 W. G. Van Name — Bermuda Ascidians. 



collected into definite bands. The sphincters of the siphons are well 

 developed. The lobes of the branchial opening- are often somewhat 

 bifid. 



The branchial sac has four rows of narrow stigmata with a con- 

 siderable number in each row. The tentacles are numerous, of 

 several sizes arranged in more than one circle, somewhat after the 

 manner described below in I). convexum. 



The intestinal loop is twisted bringing the large globular stomach 

 to the dorsal side of the abdomen. The so-called hepatic gland sur- 

 rounding the intestine is confined to a very short portion of its 

 length and consists of short tubules of rather large diameter with 

 expanded ends closely clasping the intestine. (Fig. 2.) 



The pyriform testes are very numerous, often 20 to 30 in number. 

 None of the specimens examined contained large eggs or embryos. 



This is not an abundant species. Five small colonies were col- 

 lected in 1898 attached to the lower part of a mass of coral. The 

 writer also obtained several colonies at Coney Island, Bermuda, in 

 May, 1901, below extreme low Avater mark, attached to stones. 

 These were in poor condition, with very few and small zooids. 



The species is probably commoner in deeper water than along the 

 shore. 



Distoma convexum, n. sp. 



Plate XLIX. Figure 16. Plate LV1II. ■ Figure 104. Plate L1X. 



Figure 118. 



Colony forming a thick, fleshy, rounded mass attached by a large 

 part of the lower surface. 



The largest colony obtained measures about 24 mm across and fully 

 as much in greatest height. The others are of proportionately less 

 height. 



The upper portion of the colony is free from included material 

 and the surface is smooth and glistening, but in the lower parts 

 there are many sand grains and shell fragments. The color of the 

 test is a smoky brown or dusky brown (due to scattered cells con- 

 taining the pigment), very soft and gelatinous yet transparent, so 

 that the zooids can be more or less distinctly seen. They are numer- 

 ous and closely placed, but no systems can be distinguished, at least 

 not in the preserved specimens. Bladder cells appear to be absent 

 from the test. 



The zooids art- perceptibly smaller than in the last described 

 species (D. capsidatum), the individual figured measuring L9 nun in 



