296 THE FOEAMINIFEEA 



the outer form of the U-shaped rod, is then fastened 

 to the other side, and the cell is complete (fig. 39). 

 Another method is to cement a glass slide through 

 which a hole has been drilled to another slide of the 

 same size, the top of the cell being covered with a 

 thin glass. For a cell of small dimensions the 

 following can be quickly made : A vulcanite ring is 

 split in halves and one of the semicircular pieces 

 cemented to a ?>" x \" glass slip. The upper wall of 

 the cell is made by affixing half of a circular cover 

 glass (cut with the point of a writing diamond) with 

 india-rubber cement. 



When the object is placed in a cell of this 

 description with sea-water, it may be viewed either 

 as a transparency, in which case, however, the 

 extended pseudopodia are seen with some diffi- 

 culty, or as an opaque object under a spot lens, 

 or a parabolic reflector. The latter method gives a 

 much better result, for the streaming of the proto- 

 plasm along the pseudopodia is well shown in this 

 way. At times the living Foraminifera seem very 

 shy, and refuse to extrude the sarcode through 

 the shell, but if left undisturbed for a short time 

 one is often rewarded by the beautiful phenomenon 

 of the living rhizopod with its extended pseudopodia. 

 The common shallow-water species Fohjstomella 

 crisjja makes a very good subject for such observa- 

 tion. 



0)1 tlie Collection and Preparation of Becent and 

 Sub-recent Foraminifera. — The deep-sea oozes are 

 principally obtained by the sounding apparatus and 



