10 Prof. Allman on the Hydroida. 



Male specimens of a Zoophyte closely resembling the above, 

 but rather more delicate, and with the polypes which bear the 

 gonophores all destitute of tentacula and mouth, so that they 

 become converted into gonoblastidia, have also occurred to me 

 in a rock-pool near Torquay. Though I am tempted to regard 

 this as a distinct species, I believe it will be safer for the present 

 to view it as a variety of Eudendrium humile. I shall therefore 

 provisionally designate it as E. humile, var. corymbifera. 



Eudendrium vaginatum, mihi. 



Zoophyte much branched, rising to about 1£ inch in height ; 

 polypary deeply and regularly annulated throughout. Polypes 

 vermilion, with about eighteen tentacula, and having the body 

 as far as the origin of the tentacula enveloped in a loose corru- 

 gated membranous sheath, which loses itself posteriorly upon 

 the polypary. 



Gonophores not known. 



In rock-pools at extreme low-water spring-tides, Shetland. 



This beautiful little Eudendrium, though in considerable abun- 

 dance, had, at the time of my finding it (August), evidently 

 passed the period of its greatest perfection, gonophores having 

 been in no instance present, while in many specimens the po- 

 lypes had fallen from the branches. In the absence of all know- 

 ledge of the gonophores, the above diagnosis must accordingly 

 be regarded as incomplete. 



Perigonymns serpens, mihi*. 



Zoophyte consisting of short simple erect stems, about 2 lines 

 in height, terminated by the polypes, and rising at short intervals 

 from a creeping stolon, which forms an irregular network upon 

 the surface of other bodies ; the whole of the stems and stolon 

 occupied by a reddish-orange ccenosarc and clothed with a deli- 

 cate transparent polypary, which does not form a cup-like dila- 

 tation at the base of the polypes. Polypes reddish-orange, with 

 about twelve or fourteen tentacula, so disposed that, in complete 



* The dismemberment of Ehrenberg's genus Eudendrium into two ge- 

 nera, Eudendrium and Atractylis, was proposed some years ago by Dr. T. 

 Strethill Wright. Dr.Wright was apparently not aware, when he gave the 

 name of Atractylis to one of these subdivisions, that Sars had already pro- 

 posed the name of Perigonymns for a genus identical with the Atractylis 

 of Wright. Dr. Wright had undoubtedly a more accurate appreciation 

 than Sars of the characters on which the separated genus should be based, 

 finding these characters mainly in the form of the polype, rather than in 

 the position of the gonophores ; but the laws of priority render necessary 

 the retention of the original name of Perigonymus rather than the later 

 one of Atractylis, 



