Prof. Allman on the Hydroida. 465 



The history of one Epe'ira Aurelia is the history of the whole 

 species. 



It works with the most consummate skill j but when it has 

 made its marvellous snare for the capture of prey, it trusts to 

 accident alone, and uses no artifice to entice that prey. So also 

 with regard to its cocoon. Nothing could be more perfectly 

 adapted to the purpose for which it is intended ; but directly 

 this beautiful structure is finished, the spider is utterly indif- 

 ferent to, and apparently ignorant of, its existence, which is 

 proved by my having always taken away the cocoons the morn- 

 ing after they were made, without producing the slightest effect 

 upon the Epe'ira. 



Thus they are governed in everything they do by an all -wise 

 and immutable law, which compels them, so to speak, to make 

 the best provision for themselves and for the protection of their 

 eggs — for the permanence and reproduction, in short, of their 

 race; and this, it would seem, is the end and aim of their 

 existence. 



Thurlow, Clapham, S., May 1865. 



LII. — Notes on the Hydroida. By Prof. Allman, F.R.S. 



I. Syncoryne pulchella, mihi, n. sp. 



In April last I obtained at Skelmorlie, on the Firth of Clyde, 

 a pretty little Corynidan Hydroid, which might have been seen 

 spreading in small patches over the bottom of the rock-pools 

 near low-water mark. It turns out to be a species of Synco- 

 ryne*, distinct from any hitherto described, and may be defined 

 by the following diagnosis. 



Trophosome. — Hydrocaulus consisting of simple stems rising 

 at intervals from a creeping reticulated stolon, and attaining a 

 height of about half an inch ; periderm destitute of annulation, 

 and only with a few shallow transverse corrugations towards the 

 base. Polypite with fifteen to twenty tentacles. Body of poly- 

 pite deep orange, becoming pale where it passes into the stem ; 

 stem orange. 



Gonosome. — Gonophores borne on short peduncles in a dense 

 cluster immediately behind the most posterior tentacles. Um- 



* The name of Syncoryne, adopted from Ehrenberg in a restricted 

 sense, is intended to embrace those species of the older genus Coryne 

 which have phanerocodonic gonophores, referable, at the period of their 

 liberation, to the type of Oceania as limited by Forbes and, still more 

 definitely, by Gegenbaur. (See a paper on the genera of the Hydroida in 

 the 'Annals of Nat. Hist.' for May 1864.) 



