218 MR. J. CASn ON NEW AND LITTLE-KNOWN 



On some IS'ew and Little-known British Preshwater Ehizopoda. 

 By James Cash, Manchester. (Communicated by John 

 HOPKINSON, F.L.S.) 



[Eead 16th June, 1904.] 

 (Plate 26.) 



In my investigation of the Ehizopodous fauna of this country 

 I have met with numerous forms, chiefly ia the lowland 

 districts of Cheshire, and in Epping Forest, Essex, which 

 do not appear to have been yet recorded as British, and 

 some which are new to science. Mid-Cheshire contains low- 

 lying areas of bog or morass, the home of many rare plants, 

 both phanerogamic and cryptogamic. These places are always 

 richest in Ehizopoda. Testaceous forms occur in consider- 

 able abundance, in wet Sphagnum, and amongst the rootlets 

 of such mosses as PMlonotis fojitana and Aulacomnium palustre, 

 the conditions favourable to their development being for the 

 most part constant. The genera represented are Difflugia, 

 Nehela, Hyalosplienia, Heleopera, Quadrula, and others of the 

 lobose type, whilst the Euglyphina occur also in great variety 

 and perfection. Most remarkable, perhaps, are some naked 

 reticularian Ehizopods, of which one is described herein under 

 the generic name Penardia. A second, and closely allied form, 

 may be referable to the same genus, but its place cannot be 

 determined without further study. 



Mid-Cheshire is remarkable for the number of old marl-pits 

 which are tliickly scattered over extensive districts. These har- 

 bour rhizopodous life in great variety. FseudocTilamys patella, 

 J^Licrogromia socialis, Yampyrellce, and numerous forms of 

 Amceba, besides various species of AcantJiocistis and other 

 Heliozoa, luxuriate amongst the surface-vegetation ; whilst the 

 ooze abounds in Peloinyxa palustris and P. villosa, associated in 

 two or three localities with Mastigamoeba aspera, E. Schulze, 

 and a variety of testaceous forms, such as Arcella and Centro- 

 pyoais. One of the most remarkable species met with in the 

 summer of 1903 was the Amoeba described under the name of 

 A.pilosa, sp. nov. Diffiugiella apiculata, gen. et sp. nov., is 

 the type of another proposed new genus, of which the pseudopodia 

 are a distinguishing feature. This and a new species of Vam- 

 pyrella were from the same locality, near Barking, Essex. 



