EYDROIDH EASTERN CANADA 349 



SESSIONAL PAPER No. 38a 



slight indication of fasciculation; main stem continuous throughout and distinctly- 

 heavier than any of the branches ; branches short and slender ; main stem and branches 

 with two to four annulations above the point where the branch or pedicel comes off; 

 branches similarly annulated at their origin. Hydrothecate pedicels arising from 

 each axil and one or two from each node, usually annulated throughout; hydrothecae 

 much deeper than wide; margin with 12 to 14 low, rounded teeth. . 



Gonosome. — Gonangia much elongated, with a distinct collar, borne on pedicels 

 that are annulated throughout. They appear in the axils of the pedicels and smaller 

 branches and at times are very numerous. 



Distribution. — St. Croix river, reef near Biological station, off Joe's point, off 

 St. Andrews point, St. Andrews island,, Chamcook harbour, Minister's island, Wolves 

 island, off Swallowtail light. Grand Manan. 



I have no doubt that this species which is common in the vicinity of the Biolo- 

 gical station is the same as A. Agassiz described as Eucope articulata but his descrip- 

 tion is not very complete, hence I have included a full description at this time. The 

 species resembles Ohelia dichotoma in its mode of branching, 0. longissima in the 

 nature and arrangement of the hydrothecse and 0. commissuralis in the nature and 

 arrangement of the gonangia. It is so much like these species in these respects that 

 unless one gets a complete fertile colony it is somewhat difficult at times to be sure 

 that it is not one of these species. It is quite possible that some of the records given 

 for these other species should have been given for 0. articulata. 



Obelia commissuralis McOrady. 



Ohelia commissuralis McCrady, Gymno. Charleston har., 1857, p. 95. 

 NuTTiN^G, Hyd. Woods Hole, 1901, p. 350. 

 Hargitt, Am. Nat., 1901, p. 382. 

 Whiteaves, Mar. Invert. East. Can., 1901, p. 23. 

 Fraser, Hyd. Nova Scotia, 1913, p. 167. 

 Nutting, Am. Hyd., iii, 1915, p. 83. 

 Distribution. — Grand Manan (Verrill) ; Canso. low water (Fraser) ; Grand Manan 

 (A. Agassiz) ; Seven islands. 



Obelia dichotoma (Linnaeus). 

 Sertularia dichotoma Linnseus, Syst. Nat., 1758, p. 812. 

 Ohelia dichotoma Hincks, Br. Hyd. Zooph., 1868, p. 156. 



Nutting, Hyd. Woods Hole, 1901, p. 350. 

 Whiteaves. Mar. Invert. East. Can.. 1901, p. 23. 

 Ohelia pyriformis Whiteaves, Mar. Invert. East. Can., 1901, p. 23. 

 Ohelia, dichotoma Stafford. Fauna Atlantic Coast, 1912. p. 73. 

 Eraser, Hyd. Nova Scotia, 1913, p. 167. 

 Nutting, Am. Hyd., iii, 1915, p. 80. 

 Distribution. — Nova Scotia, Metis (Dawson) ; St. Andrews, Gaspe, Seven islands 

 (Stafford); Canso, low water (Eraser); Grand Manan (A. Agassiz); Joe's point, east 

 of Spruce island 17 fathoms, Brier island, 33 to 39 fathoms. 



Obelia flabellata (Hincks). 

 Campanidaria flabellata Hincks. Ann. and Mag. Nat. Hist., 1866, p. 297. 

 Obelia flabellata Hincks, Br. Hyd. Zooph., 1868, p. 157. 

 Nutting, Hyd. Woods Hole, 1901, p. 350. 

 Stafford, Fauna Atlantic Coast, 1912, p. 73. 

 Nutting, Am. Hyd. iii, 1915, p. 84. 

 Distribution. — St. Andrews, Seven islands (Stafford) ; between White and Spruce 

 islands. 



