44 THE ROYAL SOCIETY OF CANADA 



somewhat agitated but if placed in a receptacle where the water remains 

 still they soon sink to the bottom. Since the water of the sea seems 

 the most favorable for spawning when there is scarcely a ripple on the 

 surface the eggs surely must be fertilized soon after ejection or not at 

 all. No doubt this seeming waste is at least partially obviated by the 

 movements of the Annelids themselves. As the female circles around 

 with a motion that has been aptly described by an observer as a "wavy 

 wiggle," the eggs are scattered right and left over an area relatively 

 large. At the same time the male with a similar undulatory movement 

 scatters the sperm, giving thereby a strong impetus to the movement 

 of the very active spermatozoa. In the denser part of the swarm 

 therefore, where these circles of distribution overlap, the chance for 

 the fertilization of each ovum is not so slim as it would at first appear. 



All of this then may be observed in the one evening if conditions 

 are favorable and was observed by Mr. Potts. Numerous repetitions 

 have merely substantiated the fact that the routine of the evening 

 in which he was an interested spectator, is practically the same as that 

 on any other evening during which the spawning occurs. With regard 

 to the distribution of Odontosyllis in space and of its swarming in time, 

 the limited extent of his observations did not serve as a satisfactory 

 basis for his rather sweeping conclusions, but it is quite true that he 

 makes a proviso for this in his paper. 



Taking in the first place the geographic distribution of Odontosyllis, 

 as Mr. Potts surmised, the limit was by no means reached in the much 

 circumscribed area near Snake and Five Finger Islands. The Hexac- 

 tinellid sponge referred to, as well as a number of other siliceous species, 

 are present over a wide area in the Strait of Georgia, an area of which 

 we have not as yet found the limits. It has been traced in a south- 

 easterly-northwesterly direction, i.e., running the same general direc- 

 tion as the strait and parallel to the eastern shore of Vancouver Island 

 and the other outlying islands, to the northwest as far as Northwest 

 Bay and Ballenas Islands, at least 15 miles from the original location 

 and to the channels between Lasqueti and Texada Islands, 20 miles 

 or more in a slightly different direction, while to the southeast they are 

 just as plentiful around Gabriola Reefs and Breakwater Island, at 

 least 15 miles away in that direction. Furthermore, Odontosyllis 

 has been found in a somewhat different kind of bottom in the chan- 

 nels between the islands east of Vancouver Island to the south of the 

 Station. In some of these instances the depth was much less than that 

 indicated in the drawing of the originally described area. Dredging 

 has not been done at a distance of much more than 25 miles from the 

 Station in this direction but this Annelid has been found in the most 

 distant of these dredgings. It would seem, therefore, that instead 



