86 BRITISH FRESHWATER RH1ZOPODA. 



When the test is erected, which is the normal attitude 

 during activity in testaceous rhizopods, two to four 

 blunt digitate pseudopodia are deployed, and the 

 movements of the organism are normal. 



Dimensions : Length 35-40 /x ; breadth 20-25 /x. 



In bogs, amongst Sphagnum ; also in moss growing 

 on moist rocks, rare. Dunham, Cheshire ; and Perwick 

 Bay, Isle of Man; August, 1891. Marsh near Sutton 

 Broad, Norfolk; October, 1908 (E. Gurney). 



The test of this interesting species is hyaline and 

 colourless. At the mouth the texture is extremely 

 thin ; the lips shade off to the finest possible edge. 

 The walls of the test being very transparent, the 

 plasma is seen to contain, amongst a varying amount 

 of granular material, minute chlorophyllous pellets, 

 with some colourless particles intermixed. 



The movements of the organism when lying on its 

 broad side are unusual amongst testaceous rhizopods. 

 Instead of erecting the test and throwing out digitate 

 pseudopodia, it very frequently emits a lingulate mass 

 of ectoplasm, which undergoes changes and exhibits 

 forms closely resembling those of Amoeba Umax when 

 in a state of activity. This peculiarity was very well 

 marked in examples from Norfolk, found in Sphagnum 

 collected by Mr. Edward Gurney. The tongue-like 

 single pseudopodium became, at times, lobed, and even 

 bifurcated at the apex, the lobes and short stumpy 

 branches quickly coalescing and getting absorbed in 

 the principal mass. The movements of the individual, 

 effected in this way, were rapid though somewhat 

 erratic. The peculiarity, being so distinctly exhibited 

 by examples from widely-separated localities, may 

 be taken as characteristic of the species. 



5. Hyalosphenia platystoma G. S. West. 



(Plate XXXI, figs. 7 and 8.) 



Hyalosphenia platystoma Gr. S. WEST in Jrn. Linn. Soc., 

 Zool. XXIX (1903), p. 114, t. xiii, ff. 3-6; AVERINTZEV in 



