RUNCINA. 611 



family. For a full account of its anatomy we refer to the 

 paper by Professor Allman in the " Annals of Natural 

 History,*" for January 1846, and to the fifth part of the 

 " Monograph of the British Nudibranchiate Mollusca." 



A. MODESTA, Lov^n. 



Plate C. C. C, %. 1. 



SUlic/er modestus, Loven, Index Mol. Scand. 



Alderia modesta, Allman, in Ann. Nat. Hist. vol. xvii. p. 4. — Spence Bate, 



Notes, p. 7, pi. 1. fig. 1. 

 Alderia amjyUbia, Allman, Brit. Assoc. Rep. for 1 844. 



This curious little animal was taken by Dr. Allman, in 

 great numbers, in salt marshes, near Skibbereen, in the 

 county of Cork. It has been figuretl by Mr. Spence Bate, 

 from specimens taken by Mr. Moggvidge and himself, 

 in Loughor Marsh, near Swansea. He represents it of a 

 pale yellowish colour ; the branchise are longer posteriorly 

 than in front. It attains the length of half an inch. 



We place the following mollusk, in all probability repre- 

 senting a distinct family, provisionally in this position. In 

 external aspect it resembles closely the Pelta of Quatre- 

 fages, and has a similar peculiar testaceous gizzard. The 

 presence of branchise, however, is a marked distinction ; 

 one which could scarcely have been overlooked by the emi- 

 nent French naturalist. 



RUNCINA, Forbes. 



Body elongated, limaciform, mantle distinct. No ten- 

 tacula. Vent central on the posterior portion of the back, 

 beneath the margin of the mantle and accompanied by 

 few, slightly pinnate branchise. Generative organs on 

 the right side. 



