PERIGONIMUS PALLIATUS. 325 



4. Perigonimus sessilis, Strethill Wright. 



Endexdru.m sessile, — Wrhjhl, in Proc. Roy. Phys. Sue. Ediii., vol. i, p. 237, pi. xii' 



figs. IG, 17. 

 Atractylis sessilis, — llri/jhl, id., p. 450. 

 PERiGo.\nius SESSILIS, — Al/maii, in Ann. Nat. Hist, for May, 18(!1.. Hhicks, Brit. Hydr. 



Zooph., p. 93, pi. xvii, fig. 1. 



TROPHOSOME. — Hydrocaulus obsolete or rudimental. Hydranths sessile, on 

 a creeping reticulated stolon, or slightly raised above it on the rudimental hydrocaulus» 

 invested as far as the tentacles with a cup-like extension of the perisarc ; tentacles 

 attaining the number of eight, equal in length, straight in extension, and then carried 

 alternately elevated and depressed. 



GONOSOME. — GoNOPiioRES sessile on the creeping stolon. Medusa with the 

 umbrella thimble-shaped, and having four marginal tentacles, alternately very long 

 and very short. 



Ilahitat. — Oil shells from deep water, and on rocks. 

 Localifif. — Firth of l-'ortli, Dr. Wright. 



I have never met with this apparently well-marked species. The diagnosis here given has 

 been extracted from Dr. Wright's description. Though the trophosome would seem to be very 

 distinct from that of Periyonimus piisillus, the medusse are described by Dr. Wright as differing 

 in no respect from those of that species, cither in size or form. 



5. Perigonimus pailiatus, Strethill Wright. 



Atractylis palliata, — Jl'riffht, in Ann. Nat. Hist, for August, 1861, pi. iv, figs. 6, 7. 

 Parigommus PALLIATUS, — AUiHan, in Ann. Nat. Hist, for May, \?>M. Hincks, Brit. Hydr. 



Zooph., p. 93, pi. xvii, p. 91. 



TROPHOSOME. — Hydeoc.vulus but slightly developed, and consisting of short, 

 closely set stems, which spring from a creeping reticulated stolon. Hydeanths very 

 minute, enveloped in a thick gelatinous coat as far as the border of the mouth, 

 tentacles eiu-ht, alternate. 



