FRESH-WATER RHIZOPODS 



in some the larger discs are scattered, not indiscrim- 

 inately, but with due regard to order, and even to 

 decorative arrangement. The regularity in the inter- 

 vening spaces approaches almost to the suggestion of 

 a power of counting on the part of the microscopic 

 particle of jelly-matter that we call the creature ! 



Fig. 42. Hyalosphenia papilio (after Leidy). Ranging from aio 1 ^ of an inch to 

 the ^jjth of an inch. 



Several of these tiny organisms seem to object to 

 either the round or oval patterns for their shells, and 

 prefer rectangular plates ! While others compromise 

 matters by introducing a few oval shapes, and by a 

 genius unfathomable by us, they construct a shell 

 which bears a close resemblance to a tesselated pave- 

 ment. The feelers or pseudopodia the creature puts 

 out extend to the length of the three-hundredth part 

 of an inch ! ! and are about the three-thousandth of 

 an inch in thickness. 



