Fam. 3, Plate 19. 



EOLIS PELLUCIDA, Alder and Hancock. 



E. gracilis, alba, pellucida : branchiis linearibus, roseis, apicibus albis, in fasciculis 5-6 digestis : 

 tentaculis dorsalibus elongatis, leviter corrugatis : angulis anterioribus pedis valde productis. 

 Eolis pellucida, Aid. and Hanc. in Ann. Nat. Hist. v. 12, p. 234. 

 Hab. On a Tubularia from the fishing-boats, Cullercoats, A. H. 



Body seven eighths of an inch long, slender, very pellucid, white. Dorsal tentacles 

 long, rather conical, approximating at the base, and of a delicate olivaceous hue with white 

 tips ; they are finely annularly wrinkled, the wrinkles discernible even when the tentacles 

 are fully stretched. Oral tentacles of equal length with the dorsal pair, and of a watery 

 transparency with white tips. Branchial long, linear, or slightly conical, bright carmine- 

 coloured, with a large patch of white at the apices. The coloured vessel is rather jagged at 

 the sides but not granular, and forms a cylindrical mass up the centre of the sheaths, which 

 extend a good deal beyond it on each side. The very extreme points are slightly pellucid, 

 but not so as to form the white into a ring as in & gracilis. The branchiae are arranged in 

 five or six clusters along the sides of the back ; the anterior clusters containing from 

 fifteen to seventeen papillae each, and forming a kind of ruff about the shoulders. The 

 second clusters are also well defined, but not nearly so numerous ; the others are smaller, 

 and nearly coalesce towards the tail. Foot pellucid, produced at the anterior angles into 

 long slender points, which are generally much recurved. The tail terminated very abruptly 

 in our specimen, but appeared to be injured. The eyes are very small; and placed nearer 

 together than usual. 



The specimen of this beautiful animal from which the description was taken was the 

 only one procured, and, though a little mutilated, it lived several days and was very active. 

 It had lost some of its papillae, but one of the larger clusters appeared quite perfect, and 

 sufficient of the others remained to show their character and arrangement. 



This species is allied to E. gracilis, but is much larger; the branchial papillae are 

 different in form and colour, and the shape of their central vessel is also dissimilar. In this 

 species the dorsal tentacles are olivaceous and wrinkled, in E. gracilis they are colourless 

 and smooth. Other minor points of difference might be cited, but those already alluded to 

 are sufficient to warrant our considering the species distinct. 



Figs. 1, 2, 3. Eolis pellucida, different views. 



4. Two of the papillee more highly magnified. 



