90 
Revision of British Mollusca . 
Distribution . Denmark ( March ), Christiania Fiord and 
Lofoten Islands, 15-100 fath. ( G . 0 . Sars). 
Synonyms . Clcelia trilineata , M. Sars, and Tritmia velata, 
CErsted. 
Fam. 10. Hermaeidae. 
Genus 1. Hermjea, Loven. 
168. Hermcea bifida (Montagu) . 
Plymouth ( Garstany , in litt.) . 
Distribution. Naples ( Costa) , Genoa (Trinchese) . 
It is H. Hancocki , Trinchese, and perhaps H. cruciatus, 
Agassiz; it is also Physopneumon carneum, Costa. 
169. Hermcea dendritica , Aid. & Hanc. 
Distribution. Naples (Costa), Genoa ( Trinchese ), Trieste 
( Graeffe ). 
It, is H. brevicornis , lutescens , and orbicularis of Costa. 
Genus 2. Alderia, Allman. 
170. Alderia modesta (Loven). 
Distribution. Sweden (Loven). 
It is Alderia amphibia , Allman. 
D. Pellibranchiata. 
Fam. 11. Elysiidae. 
Genus Elysia, Risso. 
171. Elysia viridis (Montagu). 
Cumbrae and Plymouth (A. M. N .). 
Yar. olivacea , Jeffreys. 
Distribution. Mediterranean (Marion &c.), Adriatic (Bergh 
&c.), iEgean ( Foi'bes ), Kiel (Meyer & Mobius ), Denmark 
(Bergh), Sweden (Loven), Norway and Finmark, 0-10 fath. 
(G. O. Sars). 
