528 Proceedings of the Royal Irish Academy. 



Zippora memhranacea (Adams). {Rissoa membranacea, Jeffreys, B.C.) 



i., ii., iii., iv., v., vi. 



Generally distributed round the coast on sea-weeds, &c. 

 Var. minor, Jeffreys. Dublin Bay (Jeffreys, '67) : Killala (Mar- 

 shall, '99). 

 Distrihution. — Loffoden I. to jiJediterranean. Canaries. 



Persephone violacea (Desmarest). {Rissoa violacea^ Jeffreys, B. C.) 

 i., ii., iii., iv., v., vi. 



i. Bangor, Belfast Lough (Thompson, '56) : Belfast Lough, between 



tide-marks, living, scarce (Hyndman, '58) : Strangford Lough, 



7-20 fms., dead, common (Dickie, '58). 

 ii. A specimen obtained at Portmarnock by "Warren was referred 



by Alder to this species (Thompson, '56). 

 iii. Ardmore (Mrs. Mackesy, f. Thompson, '56) : E. I. A. Exp., 1886, 



Glandore Harbour, 4 fms. (Chaster, '98). 

 iv. Bantry Bay (M'Andrew, f. Thompson, '56 ; Barlee, f . Jeffreys, '67 ; 



Marshall, '99) : E. I. A. Exp., 1885, 1886, 4-79 fms. (Swan- 



ston, '86, Chaster, '98) : Kenmare Eiver (Praeger, '99). Yar, 



ecostata, Jeffreys. Bantry Bay (Marshall, '99). 

 v. Kilronan, Aran I. (Standen, '95) : Connemara (Farran, f. Alder, 



'44 ; &c.) : Achill I. (Mrs. Tatlow & Praeger, '98). 

 vi. Carrahubbuck, amongst the rocks (Miss A. Warren, '92) : Killala 



Bay (Marshall, '99) : Bundoran (Marshall, '99) : Narin, co. 



Donegal (Mrs. Tatlow, '99). Yar. ecostata. Killala Bay 



(Marshall, '99). 

 Pistrilution. — Loffoden I. to Mediterranean. Madeira. Canaries, 



Rissoa Guerini, Eecluz. [Rissoa costulata, Jeffreys, B. C.) 



. . iii., iv., . . 



iii. Cork (Jeffreys, '67): E. L A. Exp., 1886, Glandore Harbour, 



4 fms. (Chaster, '98). 

 iv. E. I. A. Exp., 1885, Dursey Sound, 20-25 fms. (Swanston, '86). 



Bistrilution. — England. Wales. Ireland to Mediterranean. Madeira. 

 Canaries. 



Rissoa par V a (Da Costa). 



i., ii., iii., iv., v., vi. 



Generally distributed on sea-weeds in the laminarian zone, and 

 very common ; also var. interrupta, Adams. 



