648 Mr. R. Guiney on some 



joint are somewliat variable, the outermost being sometimes 

 scarcely more than half as long as the inner one, as figured 

 by Mrazek, but usually it is about two-thirds of the lengtli, 

 as in var. luenensis. In the second joint the innermost seta 

 is long and slender, as invar, luenensis, whereas Mrazek figures 

 it as a minute spine. 



I have met with this species in three localities in Norfolk 

 — namely, Flordon Common near Norwich, Buxton Heath 

 (Hevingham), and Holt Lowes. At Flordon it was found in 

 calcareous mud from a pool, nearly dry, but in the other two 

 places it was living in Sphagnum-moss, and it is probably to 

 be regarded as a species preferring Sphagnum and water in 

 which Desmids occur. 



Tlie resemblance between this form and G. praegeri, 

 Scourfield, which Mr. Scourfield has recently described from 

 a single female taken on Clare Island *, is very close, but the 

 form of the furcal rami and the presence of hairs inaiead of 

 spines on the anal operculum in G. praegeri^ together with 

 the divergence of the furcal setse, sufficiently separate the 

 two species. 



2. Canthocamptus weberi, Kessler. 



Kessler, Zool. Anz. xliv, 1914, p. 474 ; Thallwitz, Zool. Anz. xlviii. 

 1917, p. 159. . 



A few specimens of this rare species were found in July 

 and August 1920 in pools on NevVton St. Faith's Common 

 near Norwich. There were at that time many small pools 

 an inch or two deep with Sphagnum growing round the 

 edges, and in most of them Moraria brevipes, Sars, was 

 abundant, but C. zveheri was only found in one or two of the 

 pools in which the bottom was covered with a thin felt of the 

 liverwort, Gymnocolen hiflata. The few specimens observed 

 were obtained by squeezing this liverwort. These pools 

 occupy dej)ressions in the heather-covered common, and are 

 generally dry in summer. The summer of 1920 being parti- 

 cularly wet and cold the pools remained supplied with water 

 throughout July and August, whereas in 1921 nearly all 

 were entirely dry in May and G. weberi was not to be found. 



C. weberi is an exceedingly small species, '38 mm. long, and 

 very closely resembles G.typhlops, Mrazek. It was described 

 by Kessler in 1914 from specimens taken in moss in North 



* Proc. Roy. Irish Acad. xxx. 1912, p. 14, 



