354 W. Cr. Van JVame — Bermuda Ascidians. 



tions than along the shore. The zooids often contain larvse in the 

 atrial cavity. 



In the Peabody Museum of Yale University there are some speci- 

 mens of Atnaroucium from Fort Macon, N. C, which appear to be 

 of this species. 



Amaroucium glahruni Verrill, from the coast of Maine, forms 

 colonies of very similar size and shape. 



Amaroucium exile, n. sp. 



Plate L. Figure 31. Plate LVIII. Figure 98. 



• The colony in this species is rounded or button-shaped. It is not 

 pedunculated and adheres by the greater part of the lower surface. 

 The edges are not abrupt as in the last described form, but rounded, 

 and the consistency of the test is not so firm. It does not generally 

 grow more than 5 or 6"^™ high and 15 or 20'""^ wide. 



The test is often quite densely crowded with coarse sand grains 

 and shell fragments, in the interior of the colon}' as well as on the 

 surface; in other cases it is entirely free from such inclusions and is 

 very transparent and almost colorless. Such colonies are very beau- 

 tiful objects, for the zooids vary from orange to an even more bril- 

 liant red than those of A. hermxidm, being sometimes bright scarlet. 



The zooids are smaller and slenderer than in A. hermudce. The 

 systems ai'e irregular. The specimen figured measured a little under 

 4mm. long including the post-abdomen, which was short in this 

 individual. 



The chief anatomical differences between this and the last 

 described species appear to be that the present one has fewer stig- 

 mata, only twelve or fourteen rows (the number in each row may be 

 slightly less also), and that in this species the stomach-wall is thicker 

 and always distinctly folded longitudinally with a variable but not 

 very large number of folds (generally about 9). 



This is a less common species than the last, and though found in 

 the same situations, occurs under stones along the shore more fre- 

 quently than A. hermudce does. The writer collected it at Coney 

 Island ; Waterloo ; and Somerset Island, among other places. It 

 was obtained both in 1898 and 1901. Many of the specimens contain 

 larvae, which begin to secrete test-substance even while still contained 

 in the atrial cavity of the adult zooid. 



This species is related to A. constellatmn Verrill of the New 

 England coast. The more brilliantly colored specimens of that 



