304 E. PENARD ON SOME RHIZOPODS FROM SIERRA LEONE. 



in the contour of the test, so far as to conceal all appearance of a 

 typical Lesquereusia* 



Something, however, of the original generic type is very often 

 to be seen, a big transparent particle, or several small ones, 

 filling a kind of notch behind the mouth, the space, in fact, left 

 between the free extremity of the tube and the body of the shell 

 (Fig. la). 



The specimens were not rare, but, like everything else in the 

 collection, the plasma was dead and decayed ; something of its 

 form, however, could now and then be distinguished, and, for 

 instance, in Fig. 7 one sees the bulk of the plasma, with a strip 

 of ectoplasm which goes along and inside the tube and expands 

 at the mouth. 



Difflugia echinulata sp. nov. (PI. 10, Fig. 8). 



If Lesquereusia miinetica showed a very peculiar appearance, 

 the Rhizopod which is to be described now is perhaps more 

 curious still, in so far as it is the only known typical Difflugia 

 which is provided with spines all along its shell. 



The test, 140 to 145 /x in length (one specimen was only 

 130 fj), might be called indifferently ovoid or cylindrical, having 

 the form of a finger, or of an acorn (Fig. 8a). About twice as 

 long as broad, rounded behind, a little narrower at the anterior 

 end, and terminating in a circular opening, it is chitinous, trans- 

 parent, colourless or yellowish, and covered with siliceous particles, 

 most of which are very minute and form a kind of felt, whilst 

 some larger ones are disposed here and there at the surface. 

 This test is rounded, not compressed, a transverse section giving 

 a perfectly circular figure (Fig. 86). 



But all around the test, beginning just behind the mouth and 

 going down to the fundus, chitinous spines are disposed here 

 and there, without any symmetrical arrangement ; they are very 

 variable in number, generally a dozen or more, and in length 

 also, most of them being half as long as the shell is broad. 

 The structure of these spines is quite peculiar. They are not 

 the result of a simple exudation of the shell, but of a develop- 



* In many of the specimens which were all dead and filled with 

 decayed plasma this peculiar structure was very indistinct ; but after 

 leaving the tests for a few minutes in concentrated sulphuric acid, all 

 became clear and very distinctly visible. 



