326 DAVID BRYCE ON 



strongly marked, are suddenly cut off and the ends of tlie ridges 

 are produced into more or less short yet conspicuous thorn-like 

 spines. The long row of 8 or 10 spines, crossing the back just 

 below the middle, is frequently supplemented by a shorter row 

 of 4 or 6 lesser spines on the hinder margin of the following 

 segment and sometimes at least by two more spines on the next 

 after that. 



The anterior margin of the first central segment seems to be 

 almost invariably furnished with a pair of rather solid-looking 

 processes, frequently slightly furcate, which stand to right and 

 left of a small medial dorsal sinus. In the variety now observed 

 the processes just described were present though shorter and 

 less furcate than usual ; but the spines of the usual long row 

 crossing the back were not developed. The skinfolds terminated 

 in angular projections which could not be called spines. Two 

 very short and blunt points seemed present to right and left of 

 the central portion of the rear margin of the fifth central 

 segment, but they could only be glimpsed occasionally. In 

 other respects the specimens seemed normal. This species 

 usually inhabits mosses growing in wet places and has proved 

 to be very widely distributed, and very variable in the number 

 and exact disposition of its spines. I do not think that a 

 spineless form has yet been recorded, and in view of the great 

 range of variation possessed by the species, I have not thought 

 it desirable to separate these specimens as a new species. 

 Some specimens approaching the type form were seen by 

 Murray (5). 



Philodina acuticornis Murray. 



The specimens referred to in 1897 as P. eryihwphthalma and 

 of which I made some sketches at the time, did not belong to 

 the species now regarded as the true P. erytJirophthalma Ehren- 

 berg. They seem rather to be indistinguishable from the 

 species, a rather variable one, described by Murray some years 

 later. Some specimens seen in the L 21 collection have also 

 been assigned to the same species, which is one of the most 

 puzzling in the genus, and one of the most widely distributed. 



Philodina nemoralis Bryce. 

 A few specimens of this moss-dwelling species, rarely found 

 in ponds, were present in the " dry tundra " (L 25). In some 



