[fraser] HYDROIDS OF THE VANCOUVER ISLAND REGION loi 



lour. The medusa buds vary in number from one (in specimens 

 with three or four tentacles) to three or four; and they are in every 

 stage of development from mere knobs to medusae which are them- 

 selves in the act of budding." 15 



In the Departure Bay specimen there were three long distinct 

 tentacles and some of the secondary medusae had tentacles of consider- 

 able length as well. It may be that this is the same species that 

 Fewkes has described as Steenstrupia occidentalisa or as Hartlaub 

 has later suggested Hybocodon occidentalis 17 but I cannot see where 

 the difference comes in between it and Hybocodon prolifer. The 

 dimensions agree with those given by Mayer and the color of the 

 manubrium, "orange-red," describes exactly the color in the specimen. 



Agassiz's description is too prolix to use in this connection, hence 

 I have taken Nutting's in toto, although, as already mentioned, I find 

 a cluster of three tentacles in the medusa instead of the one tentacle 

 that he describes. The drawing of the hydroid is taken from Agassiz. 



Sub-order CALYPTOBLASTEA 



Hydroids with hydranths protected with hydrothecae and gono- 

 phores protected by gonangia or similar structures. 



Family Campanularidae 



Trophosome. — Hydrothecse campanulate, never sessile, never 

 adnate to or immersed in the stem or branches, diaphragm always 

 present; hydranth with trumpet-shaped proboscis. 



Gonosome. — Gonophores producing sporosacs or free medusae; 

 the medusae when produced usually have otocysts and have the 

 ovaries along the course of the radial canals. 



Key to the genera of Campanularidae found in the Vancouver I. 

 region. 



A. Gonophores producing sporosacs in which the planulae are de- 



veloped. 



a. Reproduction by sporosacs which remain within the gonan- 

 gium during the development of the planulae . . .Campanularia 



b. Reproduction by sporosacs which are extruded into a sac at 

 the summit of the gonangium, in which sac the planulae are 

 developed Gonothyrœa 



B. Gonophores producing medusoids without mouth or digestive 



cavity Eucopella 



15 As above in 13. 



16 Bull. Essex Inst. vol. 21, no. 7, 1889, p. 107. 



17 Zool. Jahrb. Suppl. 6, 1905, p. 545. 



Sec. IV, 1914—10 



