38 



HYDROIIJA II 



has evidently on several occasions been confused with Halcciuin scufuni. The same applies in part 

 to certain of the records from southern waters, where the species has undoubtedl\- often been mixed 

 up with Haleciuvi Beanii. 



Halecium Beanii Johnston. 

 1847 Halecimn Bemiii, Johnston, A history of the British Zoophytes p. 59, pi. 9, figs, i -2. 



Upright densely built colonies with polysiphonic, fairly robust main stem, and monosiphonic, 

 pinnately ramified outer branches; the ramification of the colony presents as a rule a main plane. The 



■ 200 m. ._._6oom. tooo m. ._ 2 ooo m. 



Fig. XII. The distribution of Halecium halecinum in the northern Atlantic. 

 In the hatched regions the Hterature denotes a common occurrence. 



minor branches are divided into slender regular internodia; the distally situate, hydrotheca-bearing 

 apophyse is almo.st of the same breadth as the branch itself, and sharply defined; the length of the 

 internodium is about 2 — 2.5 times the distal breadth (iuchuling apophyse). The hydrothecc-e small, 

 bounded on the lower side by a slight diaphragm. The primary hydrothecje are hardly more than 

 an aperture in the apophyse, and the hydranth is evidently very soon renewed; the basal chamber of 

 the secondary hydrotheca is symmetrical, with a distinctly marked basal expansion; above this the 

 hydrotheca stalk is narrowest, its breadth increasing slightU- from there until it passes over into the 

 somewhat obhquely set hydrotheca; the latter is a little broader at the aperture than at the diaphragm; 

 opening margin not outward curved. 



Gonotheca; of medium size, proceeding from the apophyse of the priuiar\ ludrothecce. The 



