BroiVH : Freshwater Rhisopods. 105 



branches like the Poplars, etc. Year after year with unfailing 

 energy, its magnificent crown rears a majestic arch, and pro- 

 jects a solemn shade ; its flowering and fruiting are annually 

 abundant, and fully sustained ; and the gaping wounds left 

 by the lopping of its larger limbs are healed up and overgrown 

 with marvellous celerity and completion. 



FRESHWATER RHIZOPODS FROM THE 

 SHEFFIELD DISTRICT. 



JAMES M. BROWN, B.Sc. 



The Freshwater Rhizopods, though an extremely interesting 

 group of microscopic animals, do not appear to receive the atten- 

 tion which they deserve. They are to be found very commonly, 

 and in almost all kinds of fresh water ; in the sediment of ponds 

 and streams and water-troughs ; amongst the floating conferva 

 and weeds ; and amongst wet moss. One needs but to collect 

 samples of sediment, weeds and moss in the field, and on arriv- 

 ing home rinse these in clear water and strain the washings 

 through fine gauze. The sediment so obtained will be found to 

 yield numerous species. Sphagnum washings are especially 

 productive, and I have found many forms amongst the green 

 growth on the overflow from water-troughs. The material 

 can be preserved in a healthy state for a considerable time in 

 shallow vessels exposed to dull light, and loosely covered to 

 prevent too much evaporation. 



The following species I have found recently in this district, 

 and they will serve as a preliminary list of the most commonly 

 ■occiuTing forms. 



Order i. — Amoebina — naked forms. 



Family Lobosa. 



Amoeba proteus (Pallus) Leidy. The 'common' amoeba 

 occurs frequently in sediment of pools and streams, and amongst 

 aquatic vegation. Burbage, Stanage, Ringinglow, etc. A large 

 form — probably Cash's var. granulosa — in a stream in Eccles- 

 all Woods. 



Amoeba villosa Wallich. Common, and generally in similar 

 situations to the previous species. 



Amoeba striata Penard. A form with a distinct external 



1909 March i. 



