OBELIA LONGISSIMA. 155 



the branches gradually decrease in length towards the apex. 

 The stem is distinctly flexuose and of a very deep horn- 

 colour, becoming black in older specimens. The branches, 

 which towards their extremities are very delicate and light- 

 coloured"^, are placed at no great distance from one 

 another, and are in most respects copies in miniature of 

 the parent stock. Their pinnee, which diminish in size 

 towards the top of the branch, are alternate, and are sub- 

 divided into numerous branchlets ; the axils of these 

 braiichlets are commonly occupied by a calycle or a small 

 shoot. The calycles are frail and deciduous, and it is dif- 

 ficult to obtain specimens on w r hich they are present. 



The C. yelatinosa of Van Beneden is clearly identical 

 with the present species, although he tells us that the rim 

 of its hydrothecse is plain. The very shallow dentation of 

 the hyaline and attenuated margin may easily have escaped 

 his observation. He has figured the sexual zooid with 

 well-developed, spherical ovaries. In masses of zoophyte 

 cast ashore after strong winds this species is often very 

 abundant, and is at once recognized by its long, dark, 

 thread-like stems. 



Hab. Rather deep water, common : Northumberland, 

 frequent (J. A.) : Peterhead and Wick, dcepish water ; 

 Gorran Haven, Cornwall, plentiful (C. W. P.): Eiley, York- 

 shire; Devon, abundant in the trawl refuse (T. H.): Port- 

 marnock. Though I am only able to give a few localities 

 for this species, I have no doubt that it is very generally 

 distributed. Till lately it had been confounded with O. 

 dic/totoma f. 



[Coasts of Belgium, most abundant (Pallas): Mouth of 

 the Elbe (Kirchenpauer).] 



* " * * snbstantia * * albida, moth'*, fenera," Pallas. 



t We owe its restoration to specific rank to the sagacity of Mr. Aider. . -;t . 



*T * - i5 ^^ 



>x 







