1897.] JfOX-MAETWE FATTNA OF SPITSBERGEN. 797 



13. Callidina pusilla, Bryce. 



Some individuals with a very large jelly-like case, mostly whitish 

 but sometimes tinged with brown, seemed structurally to be insep- 

 arable from the abo^■e species, the type form of which, as repeatedly 

 found in England, constructs a very small and meagre tube. My 

 correspondent Forstmeister L. Biltinger mentioned to me some 

 years back that he had found a variety with a large case and had 

 provisionally named it " textrix," a name which may w^ell be 

 adopted for it as rather more than usually appropriate. 



The case was flask-shaped, sometimes flattened on the ventral 

 side, nearly twice as long as the feeding rotifer, and sw^elling up 

 above and behind the trunk. The young individual will sometimes 

 settle down on the side of another case, and thus several may 

 come to form a single mass. 



14. Caliidina coenigera, Bryce. 



Many species of OaJUdina so closely resemble each other in the 

 normal or extended position, that it is necessary for identification 

 to isolate every doubtful specimen and wait until it is sufficiently 

 re-assured to feed whilst under observatiou, for it is only in the 

 feeding position that the most distinctive features of such forms 

 can be seen. Many, and especially the rarer forms, are exceedingly 

 timid, and with such it is commonly useless to look at them again 

 for several hours after isolation. One such doubtful specimen 

 had been thus set aside for a week before I saw it feeding, when 

 it showed itself to belong to this very abnormal species, which I 

 originally described from a single specimen found at Bognor 

 in Sussex. Some years later a second specimen w as met with in 

 moss collected in Buckinghamshire. The present is the third speci- 

 men found, and proves that the species, if rare, is at all events widely 

 distributed. The ci'eature lodged itself among debris and squatted 

 in a most irregular manner, so that no sketch could be obtained. 

 The figure already published gives a fair idea of the distinctive 

 ' horns,' a structural peculiarity not approached by any other 

 species j'et known. 



When extended, this specimen measured 0'347 mm., and the 

 mastax formula was 2/2. I again found the rostral lamellae 

 unusually large and conspicuous. 



15. Callidin A PAPILLOSA, Thompson. 

 Some half dozen examples. 



16. Callidina hasita, Bryee. 

 Three specimens. 



17. Adineta yaga, Davis. 



A few examples of the form I (3) have named var. minor, having 

 the face narrower than long. This form, which in my experience 

 is the more common, is, I understand from Mr. Davis, the type 

 as known to him. The var. major was not represented. 



pEOC. Zooi. Soc— 1897, No. LII. 52 



