Hydroida from Iceland. 147 



to the same excellent observer, to the great depth of 300 

 fathoms. On the whole, the Lafoeid» may be regarded as a 

 deep-water group, and as most richly developed in the 

 northern seas, so far as our present knowledge goes. 



In the Icelandic dredgings they occur in profusion, and most 

 of them attain a remarkable size. In the present paper I shall 

 describe a new species (Lafoea grandis) which is a veritable 

 giant amongst its pigmy kindred, its calycles being nearly 

 three times as large as those of the well-known L. dumosa. 

 The representatives of Calycella syringa are about twice as 

 large as those wiiich may be met with on our own coasts. 

 Calycella pygmcea * as found amongst the icebergs lias almost 

 ceased to deserve its name. I may also mention that Labrador 

 specimens of Lafoea pocillum are about twice the size of others 

 obtained at Oban. And the larger growth is not confined to 

 the Lafoeidae ; a gigantic variety of Sertularella polyzonias is 

 also present, the calycles of which are very nearly three times 

 as ample as those of the normal form, while the Avhole habit is 

 singularly robust. Serhdarella tricusjndata, a distinctly north- 

 ern form and the principal element of the Icelandic dredgings, 

 exhibits the greatest luxuriance and beauty, and bears in 

 amazing profusion the reproductive capsules, which frequently 

 line the branches throughout their whole extent. 



What may be the cause of this unusual development I 

 cannot pretend, with my present information, to decide ; but 

 he fact is undoubted. 



The following is a list of the species : — 



Subkingdom COELENTERATA. 



Class HYDROZOA. 



Order Hydroida. 



Suborder THECA^ORA. 



Family Campanulariidae. 



Campanularia volubilis, Linn. 

 Abundant on Sertularia &c. With capsules. 



* In my ' History of the British Ilydroid Zoophytes ' I have ranked 

 this species doubtfully amongst the unoperculated forms which constitute 

 tlie ffunus Lafoea. liut 1 luivo ascertained that it is in fact provided with 

 an operculum ; and it must therefore be transferred to the genus Calycella. 



