96 KELLIAD^. 



examination ; Mr. Alder, Mr. Clark, and M. Deshayes 

 have independently examined its structure with care. It 

 is of a white colour, and has the mantle closed posteriorly, 

 gaping in front, where the broad-based, strap-shaped, 

 stout foot is protruded. Its margins appear to be quite 

 plain and free from tentacles. Anteriorly they are pro- 

 duced so as to form a hyaline, tube-like canal, differing 

 from that of Kellia suborbicularis, as was first observed by 

 Mr. Alder, in being open below. Into this anterior 

 siphon-like organ the foot is sometimes pushed. The 

 anal aperture is not prolonged into a tube. According 

 to Mr. Clark, this animal is viviparous, and in the month 

 of July he found its ovarium full of perfectly-formed, 

 minute testaceous young. This is quite a new fact in 

 the economy of these bivalves, and very interesting as 

 reminding us of a similar habit in the C^las, to which 

 the sub-genus Poronia (as well as Kellia proper) bears a 

 striking external resemblance. 



This is a strictly littoral species, living gregariously in 

 the crevices of rocks, among congregations of barnacles 

 and the roots of Corallina, LicMna, and Fucus, between 

 tide-marks. It is not so generally diffused as it is locally 

 plentiful. Among localities may be enumerated Torquay 

 (S. H.) ; Burrow Island (S. H.) ; Herm near Guernsey 

 (S. H.) ; Exmouth (Clark) ; Dartmouth, where some 

 specimens occurred in the crevices of a mass of stone 

 dredged from seven fathoms, — a very exceptional locality 

 (M 'Andrew and E. F.) ; Whitesand Bay and Falmouth 

 (Jeffreys) ; Glamorganshire, Tenby, and St. David's (Jef- 

 freys) ; Isle of Man, very abundant all round the coast 

 wherever there is rock (E. F.) ; Scarborough (Bean) ; 

 Northumberland, near Whitley (Alder) ; and at the roots 

 of Lichina pygmaa on the rocks below Bamborough Castle 



