VAN NAME: COMPOUND ASCIDIANS. 
3G3 
The test is practically free from sand, and though not verv transpar- 
ent, it allows the anterior part of the zooids to be more or less distinctly 
seen through its substance. It is of a translucent yellowish white or 
yellowish gray color in the preserved specimens, while the tissues of the 
zooids are opaque yellowish white. The zooids are evidently not 
arranged in systems, their atrial orifices opening separately on the 
outer surface of the colony, yet they are in many cases very regularly 
distributed, forming evident rows from the base to the apex of the 
colony. In some of the specimens the anterior ends of the zooids tend 
to project slightly above the level of the surface of the colony. In the 
living specimens this no doubt occurred to a much greater extent. 
In all the specimens the zooids are violently contracted and contorted, 
and examples which are approximately straightened out are hard to 
Text-fig. 4. — Pulycitor kiikenthali (Gottschaldi). Three colonies. Natural size. 
find. Such examples measure in their shrunken condition only about 
5 mm. to 7 mm. in length, but it is very evident tliat this gives little 
idea of their natural size, which must have been at least two or three 
times as great in living, moderately expanded individuals. 
The mantle is very muscular, especially on the thorax, where there 
are numerous strong longitudinal muscle bands, and underlying these, 
a dense layer of transverse fibers, which, however, form much less 
distinct bands. As a result of the contraction of the powerful longi- 
tudinal muscles the thorax in the preserved specimens is commonlv 
broader in a dorso-ventral directicjn than it is l(mg, and the long slender 
abdomen becomes also greatly shortened, the esophagus and intestine 
becoming irregularly plicated transversely. The branchial J^and 
