168 W. MILNE ON THE 



attention to bosses at the time I found it. Otherwise, the two 

 agree extremely well. 



Habitat. — Rock moss, Kamaehs farm, Uitenhage district. 



Habrotrocha pertinax sp. no v. 

 PL 12, figs. 12-12a. 



Specific Characters. — Very small, narrow at front and widening 

 gradually to the rump ; hyaline. Rostrum narrow with promi- 

 nent double lamella. Antenna short, about one-third neck 

 width. Teeth three to four, quite large for pellet makers. Rump 

 heavy. Foot of apparently three segments. Spurs sharp cones, 

 divergent, no interspace. Corona to collar as 4 to 7J. Sulcus a 

 mere slit. Upper lip a broad mass rising right up, and projecting 

 slightly over back of wheels. Trunk clearly stippled. Size, 

 1/1 20th inch. 



This is an active little animal. It keeps on for a long time 

 creeping fast with a slither or glide, sometimes for hours without 

 resting. It is so small that it is quite easily overlooked, and 

 when searching particularly for it in a new slide I hardly think 

 I ever found it, as it apparently keeps out of sight in the debris, 

 or rolls up in a ball after being disturbed. Only after a day or 

 two, when examining the slide, by chance one might be caught 

 sight of in the open. 



The corona is scarcely more than half the collar width. When 

 the head is thrown back it has the appearance of Scepanotrocha 

 (5), as then the edges of the wheels just show above the big 

 upper lip. Seen horizontally, the upper lip is a broad mass right 

 up to the top of the corona, but seems to turn slightly in at the 

 middle. The edge of the upper lip, rising up from the collar, 

 seems to just pass over the back of the wheels, and to form a 

 sort of cradle for the back of the corona. When it is feeding 

 — lying on its back — with the head bent up above the hori- 

 zontal, the square, broad outline of the upper lip can be seen 

 just above and behind the wheels, also the part mentioned above 

 appears triangular in outline over the wheels. It usually stands 

 straight up on its toes when feeding, and keeps in one position, or 

 very slowly turns its head ; it keeps stretching and stretching 

 till sometimes the length is considerably greater than the creeping 



