536 THE FUR SEALS OF THE PRIBILOF ISLANDS. 



Fig. 13. Branchial tentacles of same. 



Fig. 14. Colony of Polyclinum glohosum, with a portion cut away. The small area at ft indicates 



aboiit the distribution of the zooids, and shows the branchial orifices, though much more 



distinctly than they can actually be seen. 

 Fig. 15. A single zooid of same species. 

 Fig. 16. Atrial languet of same, seen from the under side. 

 Figs. 17A and 17B. Two sectioned colonies of PohjcUnnm pannosum, 17A sliowiug the zooids in their 



normal form and position, and 17B the degenerated zooiils. Tin; (liaracteristic ragged 



surface of the colony is shown at y, 17B. 

 Fig. 18. Portion of a /ooid of P. jfannosum. 

 Fig. 19. A colony of ApUdiopsis jordani with an individual of Dendrodoa siihpeduncHlatn, D. S., imbedded 



in it. 

 Fig. 20. A zooid of A. jordani. The post-abdomen outlined in this specimen is unusually short. 

 Figs. 21, 21A, and 21B. Portions of dift'ercut zooids of Amarouclum kincaidi. 21A and 21B drawn par- 

 ticularly to show the equivocal character of the irregularities in the stomach walls. 

 Fig. 22. A colony of Amiiroiicium snodi/rassi. The specimen is seen from its base, B, and one of its 



precipitous edges, on which latter the zooids s are visible tlirough the semitransparent test. 

 Fig. 23. Stomach and small portion of intestinal loop of Amaroitoium snodgrasai. 

 Fig. 23A. Anterior end of zooid of same species, seen from inside. 

 Fig. 23B. A few of the remarkably long, narrow stigmata of same species. 

 Fig. 24. A colony of Amaroiiciitm 2>rihilovcni<c. 



Fig. 25. A single zooid, the posterior part of the post-abdomen wanting, of the same species. 

 Fig. 26. A colony of Sjinoicum irregulare. 

 Fig. 27. The cut surface of one of the lobes of a colony of same species, showing the packages of 



embryos, c, imbedded in the test. 

 Fig. 28. A zooid of S. irregulare. 



Plate LXXXVI. 



Figs. 29, 29a, and 296. Ovarian ova of S. irregulare, 29 and 29b containing ingested cells. X 360. 



Fig. 30. An ovarian ovum, presumably nearly ready for maturation. X 360. 



Fig. 31. Two-celled stage. X 360. 



Fig. 32. Morula? early gastrula stage. X 360. 



Fig. 33. Embryo well advanced in metamorphosis. This from one of the caviticvs containing embryos 

 only. X 40. 



Fig. 34. Small portion of the test of an old embryo. The cellular masses, x, are the same as the 

 bodies shown at x, fig. 33. These probably belong to the test of the embryo itself. The 

 mass I/, k. is imbedded in the test, and is without doubt a cluster of the mesenchymatous 

 yolk containing bodies found in the parental post-abdomen, m. /. appear to bo muscle 

 fibers derived from the mantle of the parent. 



BIBLIOGRAPHY. 



BoNNEVIE, KKI.STINE. 



1896. Ascidiae .Simplices og Ascidiae Compositae. Den Norske Nordhavs-Expedition, 1876-1878. 



XXIII, Zoologi. 

 Edwards, Mii.ne. 



1846. Observations sur les ascidies compo.secs des Crttes de la Maiiche. Mdmoiros de I'Academie 



royale des sciences do I'lnstitute de France. T. XVIII, 1846. 



GlARD, A. 



1872. Recherch('s sur les Ascidies comi)os(^es, ou Syuascidies. Th(>ses, 1872. 

 Hancock, Ai.hany. 



1868. On the Anatomy and Physiology of the Tunicata. Journal Linnoan Society — Zoology. 

 Vol. IX, 1868. 

 Heli.er, Causii,. 



1877. Untersuchungen iiber die Tunicaten des Adriatischen und Mittolm<^er»'s. Ill (1) Alitheil- 

 ung. Denkschriften d. kais. Akad. d. Wissensch. Wien, Math.-naturwiss. Classe. Bd. XXXVII, 

 1877. 



