310 NATURAL HISTORY OF 



A. liexagonum {T. H., Aid.), A. parasiticum (Smitt), 

 Hab.: Scotland {I) aly ell), J) eY on and Cornwall, Menai 

 Straits, Isle of Man {T.H.), Northumberland (Aid.). 



A species not uncommon on stones and shells within 

 and below tide-marks. It forms whitish or yellow 

 incrustations. The zooecia are hexagonal, with distinct 

 septa. The ova are opaque white, and arranged in a 

 circle within the ovicels, which are numerous and 

 scattered over the colony. 



7. A. ALBiDUM, Alder. 



Hab.: Northumberland (Aid.), Ilfracombe {T.H.). 



This species is incrusting, and yellowish-white in 

 colour ; and in certain stages looks, according to Mr. 

 Alder, " like a cluster of separate animals. The poly- 

 pides are prominent, ventricose, flask-shaped, becoming 

 erect towards the aperture, which is truncated when 

 contracted.^^ 



8. A. POLYOUM, Hassall. 



Sarcochitum polyoum {Hassall, D. L., G.J., McA.). 

 Hab. : Dublin Bay (iTassaiZ), Northumberland i^Ald.). 

 Probably a form of A. mytili. 



9. A. PARASITICUM, Fleming. Plate XXIII. fig. 1. 

 Alcyonium parasiticum {Fleming, De Bl.). 



Hab. : St. Andrews {McL), Northumberland {Aid.), 

 Cornwall {B. Q. C), Menai Straits, South Devon {T.H). 



This species becomes so impregnated with earthy 

 matter as to resemble a blackish-brown coating of 

 earth on corallines, hydroids, &c. It is about ^ inch 

 in thickness. 



Couch says the appearance so much approaches 

 what is observed in many worms, as in Sahellce, that 

 he was inclined to think it the work of an annulated 

 animal rather than that of a zoophyte. 



