W. Lilljeborg on the Genera Peltogaster and Liriope. 171 



2. Peltogaster sulcatus, n. sp. PI. IV. fig. 14. 



Diagn. Acetabulum pone medium situm, simplex, margine expanse-, 

 radiate- . Infra inter acetabulum et aperturam corporis anteriorem 

 magnam et marginatam bisulcatus. — Longit. circ. 7-5 mill. 



This species is much smaller than the preceding, and has a 

 more cylindrical form. It generally appears to be thicker at the 

 part where the organ of adhesion is situated. The two extremi- 

 ties of the body are curved downwards, though not much. The 

 part behind the organ of adhesion is shorter and more slender 

 than the anterior part. There are some transverse folds in the 

 vicinity of the organ of adhesion, and between this organ and 

 the anterior aperture there are two longitudinal parallel furrows. 

 Sometimes there are in this part several longitudinal folds in 

 the skin, which is rather thick and scarcely transparent. 



The organ of adhesion is well developed, though much smaller 

 than that of the preceding species. The neck is very distinct, 

 and the margins are turned outwards and present radiating 

 furrows. In the middle there is an elevation, in which a small 

 orifice (the mouth) is visible, surrounded by a brown horny 

 ring. The rest, although apparently of more solid consistence 

 than the skin, is of the same colour ; there is no shield at its 

 base, which is surrounded by a harder raised border of epidermis, 

 and beyond this there is in the epidermis a streak of a more solid 

 and more opake substance. 



The anterior part of the body presents a short tube, curved 

 downwards and provided with longitudinal folds ; this surrounds 

 the large aperture of that part. Above this aperture the author 

 has found a small empty space between the skin and the sac of 

 eggs which fills the body. Specimens preserved in spirits are of 

 a yellowish- white colour. 



This species has been found upon Pagurus cuanensis and P. 

 chir -acanthus, on the coasts of Norway. Dr. G. Lindstrom met 

 with as many as seven upon the same individual of P. cuanensis. 

 The anterior part of the body is usually directed a little to the 

 right above the abdomen of the Pagurus. 



3. Peltogaster microstoma, n. sp. PI. IV. fig. 15. 



Diagn. Acetabulum pone medium situm, minimum, margine vix 

 expanso et radiato. Apertura anterior minima, vix visibilis, neque 

 marginata. — Long. 5-6 mill. 



This species is smaller than the preceding, and is distinguished 

 from both the others by the smallness of the organ of adhesion 

 and of the anterior aperture. Its form is very variable : it is 

 sometimes cylindrical (fig. 15), sometimes much flattened, pro- 

 bably owing to the varying pressure of the surrounding shell. 



12* 



