38 BRITJSH FEESHWATER EHIZOPODA. 



14. DifQugia brevicolla sp. nov. 



(Plate XIX, figs. 12 and 13; and fig. 55 in text.) 



Test spherical, with a short neck, the extremity of 

 which is truncated to form the circular mouth, its 

 margin plain, without contraction or dilatation ; struc- 

 ture chitinoid, with a surfacing of irregular scales or 

 these with an admixture of small diatom-frustules, and 

 occasionally a few sand-grains ; sometimes with a single 

 quartz particle of larger size adhering to the crown. 

 Characters of the plasma, pseudopodia, and nucleus 

 unknown. 



Fig. 55. — Sifflugia irevicolla. Empty test from Dunham Marsh, x 280. 



Dimensions : Diameter 70-90 fx ; of mouth 35-40 /x. 



In deep ditches of peat-bogs and open ponds amongst 

 decaying vegetation. Risley Moss, Lancashire, 1903 ; 

 Chilford and Dunham, Cheshire. 



In peat-bogs the test of this species is found to take 

 on the brownish colour of the water, its opacity increas- 

 ing with age. In ponds, on the contrary, it does not 

 differ in colour from other Diffiugise of similar structure. 

 No example was fo\ind in the active state, but amongst 

 the numerous examples from the first-named locality 

 two were observed in conjugation. 



1 5. Difflugia orbicularis sj). nov. 



(Plate XX, figs. 6 and 7.) 



Test minute, spherical, with a short neck, chitinoid, 

 yellowish, or lightish brown, destitiite of incrustation ; 



