igil] ASCIDIANS FROM THE COASTS OF CANADA. 133 



C. joannae (Herdman). 



Syn. — Cynthia coriacea Stimpson, Proc. Ac. Phil., ann. 1864, p. 160. 

 Styela joanncB Herdman, Tr. Liv. Biol. Soc, vol. XII, p. 264. 

 Styela stimpsoni Ritter, Ann.N. Y. Ac, vol. XII, p. 602. 



Numerous specimens from Departure Bay, Ucluelet, China Hat and 

 Banks Island, attached to rocks &c., from low tide mark to at least 20 

 fathoms. 



From the abundance of the material in my possession, all, as far as 

 examined, agreeing with Ritter's description, I judge that Herdman's 

 and Ritter's species are the same and that Herdman was mistaken in 

 describing the dorsal lamina as being a 'plain membrane.' Stimpson's 

 name was preoccupied by Alder & Hancock in 1848. 



Family — TethyidcB. 



[Halocynthiidce sen Pyuridce, auct., non Tethyidce Hartmeyer, 1909] 



In my opinion, the valid type of the genus Tethyiim Bohadsch is the 



Ascidia papillosum of Linn6. Cynthia and Halocynthia will then be 



absolutely synonymous with Tethyum and are to be replaced by it. 



HalocynthiidcB and Pyuridce are to be replaced by Tethyidce. 



Genus, Boltenia {sens, nov.) 



Syn. Boltenia auct. par t.-\- Halocynthia auct. part. 



Body elongated parallel to a line joining apertures. Surface covered 

 with simple or branched spines. Short, channeled, siphonal spinules. 



Aperture of dorsal tubercle bent, opening between horns directed 

 toward right side. Dorsal groove with languets. At least 6 folds on 

 each side, the second and sixth, counting from above, being the smallest. 

 Stigmata transverse, arranged in longitudinal rows, which are traversed 

 from end to end by the longitudinal bars. 



One gonad on each side, the left in the intestinal loop. The ducts 

 are at the posterior end of each. Each consists of an axial ovary and 

 peripheral testicular lobes. 



Type species — B. ovifera (L.) 



This is a very sharply defined group and includes only a few of the 

 stalked forms that have been referred to this genus. It appears to be 

 confined to the Arctic and Subarctic regions. In addition to the species 

 mentioned in this article, it includes B. thompsoni Hartmeyer of Bering 

 Sea. Some of these species have been placed in the old genus Boltenia 

 and some in the genus Halocynthia or Pyura. 



B. echinata (L.) 



Syn. Cynthia echinata plur. auct., non Boltenia echinata Ritter, 1907. 



A few specimens were obtained in 10 to 20 fathoms, stony or shelly, 

 at Departure Bay. Hartmeyer has recently (S.-B. Ges. naturf. Freunde 



