DIPHASIA FALLAX. 251 



processes, and protected by four long and pointed seg- 

 ments, into which the upper part of the capsule is cleft. 

 These originate a good way down, and may be traced in 

 an early stage of the development ; they are not adherent, 

 but converge above and so close the aperture, opening 

 readily for the passage of the embryo. We have here a 

 modification of the structure already described in the case 

 of D. rosacea. The circulation of the nutrient fluid may 

 be traced in the tubes which surround the marsupium. I 

 have seen as many as six finely ciliated planules moving 

 freely about within the cavity of the sac. 



A specimen in my possession bears capsules of both 

 sexes, the female occupying the upper portion of the 

 shoot, and the male being distributed over the lower 

 branches, another case of departure from the dioscious 

 condition which is usual amongst the Hydroida. 



Hub. Commonly parasitic on other zoophytes, to which 

 it binds itself by means of its numerous tendrils. It is a 

 northern species, ranging from the coast of Yorkshire to 

 Shetland, and an inhabitant of deep water. Filey, abun- 

 dant (T. H.) : Scarborough (Mr. Bean's collection con- 

 tains very splendid specimens, composed of many large 

 shoots united together) ; Northumberland and Durham, 

 frequent (J. A.) : Firth of Forth, plentiful (Dr. Cold- 

 stream) : Loch Fyne (A. M. N.) : coast of Aberdeen 

 (Macgillivray) : Peterhead, plentiful ; Wick, much rarer 

 (C. W. P.): Orkney Islands, 35 fathoms; Buchanness, 

 40 fathoms (Lieut. Thomas): Hebrides; Shetland, 40 

 fathoms (A. M. N.). 



[Tromso, in 30 fathoms, rare ; commoner at Bergen on 

 stems of Laminaria (Sars) : Grand Manan ; " a few speci- 

 mens, probably of this species, were taken in deep water' 3 

 (Stimpson) : Massachusetts Bay (Agassiz).] 





