On two new British Nudihranchiate Aiollusca. 517 



tioned genera are neither sponges nor Foraminifera, but the 

 nearest allies of the Hydractini^ with a calcareous skeleton, 

 and thus attach themselves to the Hydroniedusai. To the same 

 group, according to Lindstrora*, belongs also the genus La- 

 hechia, M.-Ed\v. & H., formerly referred to the order of the 

 Zoantliaria tabulata. 



LXIV. — On two new British Nudihranchiate Mollusca. 

 By the Kev. A. M. Norman, M.A. 



Eolis sanguinea^ n. sp. 



Body narrow, and tapering behind to a very fine point, red, 

 tliis colour more intense on the anterior portion of the animal 

 as far back as the heart. Dorsal tentacles placed near to each 

 other at their bases, smooth, of a blood-red colour, with pale 

 tips. Oral tentacles set far apart, somewhat longer than the 

 dorsal pair, red, but paler in colour than the dorsal. Eyes 

 situated close behind the dorsal tentacles. Branchice very 

 numerous, distributed in about eighteen transverse rows ; 

 there are as many as twenty branchiaj in the first transverse 

 row, and ten in the sixth or seventh row ; they are short, of a 

 blood-red colour, with the central vessel very dark, and their 

 tips, on the other hand, white ; they extend forwards round 

 the bases of the dorsal tentacles. The tail tapers away to a 

 very fine point behind, which, however, hardly appears be- 

 yond the ultimate branchiss. Foot of a pale flesh-colour, with 

 short tentacular points in front. Length \^ inch. 



A single specimen of this very beautiful new Eolis was 

 taken August 26, 1874, at low water, spring tides, on the 

 islet known as Innislacken, which is situated at the entrance 

 of Roundstone Bay, Connemara. 



Eolis sanguinea is a remarkably active little fellow, crawling 

 along with considerable rapidity. It is very distinct from all 

 described species. It belongs to Eolis (proper) as distin- 

 guished from its subgenera. Eolis (proper) includes only 

 three British species — imjpillosa^ glauca, and Alderi. Our 

 new form comes nearest to E. glauca^ from which it differs in 

 its more attenuated form, in its more numerous transverse 

 rows of branchiaj and more numerous branchite in those rows', 

 in its more brilliant body-colour, and its branchise being 

 blood-red instead of " sage-green." Although tapering to 



* .Villi. .^ :.Ia,u-. Nat. Hist. 1876, vol. xviii. p. 4. 



