NO. 1989. ASOIDIANS FROM NORTHEASTERS PACIFIC— RITTER. 505 



Fig. 24. Styela sabulifera, left side view, mantle removed to expose the parts. X 3. 

 gon., gonad; st., stomach. 



25. Hypophysis, branchial tentacles, dorsal lamina, and branchial sac of Styela 



sabulifera. b. t., branchial tentacle; d. I., dorsal lamina; hy., hypophysis; 

 i. I. v., internal longitudinal vessels. 



26. Gonad of right side of S. sabulifera. ov., ovary; tes., testis. 



27. Dendrodoa tuberculata. A gonad of the most highly branched form, gon., 



gonad. 



Plate 35.. 



Fig. 28, 29. Corella japonica, right and left side views respectively; test removed 

 X 2. b.s., branchial siphon; int., intestine; m.f., muscle fibers; ov., ovary; 

 s. d., sperm duct; st., stomach; tes., testis. 



30. Branchial sac of C. japonica. d. I., dorsal lamina; i. I. v., internal longitu- 



dinal vessels; s., stigmata. 



31. Corynascidia herdmani, right side, surface view. X 1. b. s., branchial 



siphon; ped., peduncle. 



32. Alimentary and reproductive sj^stems of C. herdmani. ov., ovary; ov. d., 



oviduct; s. d., sperm duct; st., stomach; tes., testis. 



33. Branchial membrane of C. herdmani. i. I. v., rnternal longitudinal vessels; 



s., stigmata; t. v., transverse vessel. 



34. Branchial tentacles and mantle muscle bands of C. lierdmani b. t., branchial 



tentacle; m.f., muscle fibers. 



35. Dorsal languets with adjacent parts of C. herdmani. ant., anterior; d. lu., 



dorsal languets; i. I. v., internal longitudinal vessels; rt., right; s., stig- 

 mata; t.v., transverse vessel. 



36. Hypophysis and small piece of peripharyngeal gioove of C. herdmani. hy., 



hypophysis; p. g., peripharyngeal groove. 



Plate 36. 



Fig. 37. Agnesia beringia, left side, test removed. XL b.s., branchial siphon; int., 

 intestine; gon., gonad. 



38. Alimentary and reproductive sj^stems of A. beringia. int., intestine; ov., 



ovary; ov. d., oviduct; St., stomach; tes., testis. 



39. Branchial tentacles, peripharyngeal groove, and hypophysis of A. beringia. 



b. s., branchial siphon; 6. t., branchial tentacle; hy., hypophysis. 



40. Whole dorsal area of branchial sac of A. beringia showing the processes on 



the transverse vessels with larger ones near the mid-dorsal line which 

 seem to take the place of dorsal languets. d. I., dorsal lamina; p., papilla; 

 p. g., peripharyngeal groove; t. v., transverse vessel. 



41. The branchial membrane of A. beringia in detail, p., papilla; t. v., trans- 



verse vessel. 



42. Phallusia vermiformis, test removed, left side. X ^- a. s., a trial siphon; 



b. p., branchial pouch; b. s., branchial siphon; ov. d., oviduct; s. d., sperm 

 duct; St., stomach. 



43. Phallusia unalaskensis, anterior end, test removed, b. s., branchial siphon. 



44. Hypophysis, branchial tentacles, and dorsal lamina of P. unalaskensis. b. t., 



branchial tentacle; d. l, dorsal lamina; g., hypophyseal gland; gn., gan- 

 glion; hy., hypophysis; p. g., perij^haryngeal groove. 



45. Branchial rnembrane of P. unalaskensis. i. I. v., internal longitudinal ves- 



sels; p., papilla; t. v., transverse vessel. 



