122 Transactions of the Canadian Institute. [vol. ix 



to the ribs. Bars, 35 to 54 on right and 32 to 51 on left side. Papillae 

 at junctions, but not between. One plication or less between successive 

 bars. From 3 to 9 stigmata in each mesh. 



Intestinal canal occupies from ys to }4 oi left side, leaving from 

 ys to J4 oi length of pharynx uncovered at both anterior and posterior 

 ends. Stomach with about 17 folds. Intestinal loop bent forwards 

 and somewhat upwards. Ovary in intestinal loop and on its right side. 

 Oviduct follows posterior margin of last bend of intestine and postero- 

 dorsal margin of rectum. Testicular lobes in a thick layer on right side 

 of stomach and scattered over both sides of intestinal loop. Vas deferens 

 on right side of first part of oviduct and in groove on the left side between 

 second part of oviduct and rectum. As a result of this, when one looks 

 at the lower side of the body (test removed) only a short terminal part 

 of the vas deferens is seen. 



In and near Departure Bay, in from 10 to 30 fathoms, locally abundant. 



Its closest ally appears to be P. longistriata Hartmeyer from Japan, 

 from which it differs in having the margin of the dorsal lamina toothed 

 and in the situation of the gonads. 



Family — Chelyosomatidae. 



As is shown farther on, the intestinal loop in the genus Chelyosoma 

 is always on the right side of the pharynx. Whether it is on the right or 

 left side of an arbitrary median plane, is of little moment. With this 

 genus brought into line, we have the utmost constancy in the position 

 of the intestinal loop with reference to the pharynx in each of the genera 

 of Ascidians. The only exceptions are those individuals that show an 

 inversio viscerum. It seems right, therefore, that the genus Agnesia 

 should not be placed in this family. 

 Corella willmeriana Herdman. 



One specimen from Elk Bay was collected by Dr. Dawson, in 1885. 



The surface is smooth. The atrial aperture is not on a distinct 

 siphon. There are 24 bars on right side of pharynx and 22 (?) on left side. 

 Spirals of infundibula are for the most part broken up into short stigmata. 



C. rugosa sp. n. 



Syn. C. willmeriana Ritter, Ann. N.Y. Ac, vol. 12, p. 604. 



Oblong, laterally compressed or more or less cylindrical. Attached 

 by posterior end or by right or left side. Apertures on same level at 

 anterior end; atrial often at the end of a short siphon. Surface irregu- 

 larly wrinkled and rough with fine irregular processes of the test. Up to 

 4 cm. long, 2 cm. wide and 1.5 cm. thick. Musculature consists of the 

 usual siphonal fibres and of longitudinal fibres extending from the siph- 

 ons for a short distance back over the body. 



