SOME ROTIFERA FROM SPITSBERGEN. 327 



mosses brought to me from the Faroe Islands by Mr. Earland 

 some years ago I found numerous examples of this easily recog- 

 nisable species. 



Philodina rugosa Bryce. 

 To this species are to be assigned some rough-skinned Philo- 

 dinae referred to in my report of 1897 as Philodina sp. 



Mniobia russeola (Zelinka) (fig. 6 a-d). 

 This large and handsome rotifer, which occurred in the gather- 

 ings of 1896 and was also seen by Murray (5), was present in 

 three collections, one from each of the three localities whence 

 moss was taken. Its presence proved specially interesting. The 

 solitary example seen in the washing of the Z 1 gathering was 

 found, on being isolated, to have within its body a vermiform 

 parasite, which was recognised as one which I had seen on two 

 previous occasions in British specimens of the same rotifer. At 

 a later date another individual from the L 21 moss was found 

 to be infected by the same parasite, and from this latter were 

 obtained some details which I had not been able to make out on 

 previous occasions. 



Mrdobia russeola is a rather stoutly built BdeUoid rotifer whose 

 body when fully extended is somewhat larviform, and divided 

 into fifteen segments, the anterior six forming the head and 

 neck, the following six the trunk (or central body), and the 

 last three a very short foot. Adult individuals are usually at 

 least 600 /x in length, and I have seen them up to nearly 800 ft. 

 long. The skin is transparent. When the animal feeds it 

 usually assumes a somewhat squatting position. When undis- 

 turbed it will often continue quietly feeding for hours with 

 scarcely any change of position. In the genus Mniobia, as in 

 most of the other BdeUoid genera, the stomach is a long sausage- 

 like organ occupying a large proportion of the cavity of the 

 trunk. It has a thick wall consisting of more or less minutely 

 granular tissue packed between two membranes or tubes, one 

 within the other, the inner lining forming cavity of the 

 stomach, the outer the actual lumen or the exterior coat of 

 this organ. Behind the stomach and usually separated by a 

 constriction controlled by a sphincter muscle, is a short bladder- 

 like intestine. Behind the intestine is a contractile cloaca, 

 which combines the functions of a contractile vesicle (as found 

 JouRN. Q. M. C, Series II.— No. 88. 23 



