SCROBICULARIA. 443 



Habitat : Tidal estuaries and brackish water on the 

 coasts of Devon, Dorset, Hants, Sussex, Kent, Guernsey, 

 and Jersey, in mud at low tides; Scarborough (Bean) ; 

 from the stomach of a wild- duck shot on Holy Island 

 (Adamson) ; Seaton (Backhouse) ; Isle of Man, " in 

 cavities of dead shells from deep water on the north 

 coast" (Forbes); Lough Larne, co. Antrim (Thompson) ; 

 Portmarnock, Dublin Bay (Rev. B.W. Adams). Per- 

 haps some of the above localities may be questionable. 

 Cherbourg (DeGerville) ; Portbail in that vicinity (Mace) ; 

 shore of the lake, and living in 35 fathoms off the Gulf 

 of Tunis (M f Andrew). 



According to the late Dr. Lukis, who favoured me 

 with a description and sketch in October 1859, the ani- 

 mal is active, and not very timid. I give his own ac- 

 count of it : " Arnold's pond contains the largest speci- 

 mens of S. tenuis ; and I discovered it in rather an un- 

 expected manner, while sifting under the water of the 

 pond the ulvce and weeds in searching for a stock of 

 Rissoa labiosa. The R. [Hydrobid] ulva also occurs 

 there. I sifted the weeds at the time of nearly high 

 tide, while the sea- water was rushing into the pond ; and 

 I imagine that the active Syndosmya was rising to the 

 surface of the mud to imbibe the fresh stream from the 

 sea, and thus became entangled in the weeds to be trans- 

 ferred to my sieve, an easy prey. I am not sure that 

 they do not become the food of the grey mullet, consi- 

 derable numbers of which live in the pond ; for while I 

 waded almost knee-deep, the fish played actively about 

 me." In the last communication that I received from 

 him (March 1863) he says, as to this species, "abun- 

 dant in streams supplying the salt-works in Guernsey ; 

 also in the mud on the shore, in company with Cylichna 

 obtusa, where there is an occasional afflux of brackish 



