244 FRESH-WATER RHIZOPODS OF NORTH AMERICA. 



Apparently the same animal lias been described by Professor Greeff 

 with the name of Heterophrys variabilis. It contained variable proportions 

 of colored grannies, green and red, together with colorless vacuoles and 

 nuclei. The body possessed a transparent, colorless envelope, defined at 

 the surface by minute linear particles. The size of the animal with its 

 envelope was 0.06 mm. 



It is probable that the forms described by Professor Schulze and Pro- 

 fessor Greeff represent different conditions of the form described by Mr. 

 Archer as Heterophrys myriapoda. 



In many instances I have observed colored Actinophrys-like animal- 

 cules, of uncertain reference, resembling Heterophrys, but devoid of its 

 cloak of protoplasm. I have suspected, however, that the latter belongs to 

 one stage of the animal's existence, and in another stage may be absent. If 

 this view is correct, it is probable that the forms referred to Actmophrys 

 picta, and those allied to it, may belong to Heterophrys. 



Animals of the same general character, probably referable to several 

 different species, are represented in figs. 1-6, pi. XLV, and figs. 7-13, pi. 

 XLVI. 



Forms like those of figs. 7-9, pi. XLVI, are not unfrequent in the 

 ponds of sphagnous swamps in New Jersey. The body of the Heliozoan 

 is commonly spherical, but capable of changing its shape. It is composed 

 of soft, homogeneous, granular protoplasm, with or without minute oil 

 molecules, colorless at the surface, bat variably green and yellowish or 

 brownish in the interior. It usually exhibits neither vacuoles nor contrac- 

 tile vesicles, and commonly a central nucleus, if present, is obscured from 

 view. The pseudopodal rays, generally fewer, are often longer and coarser 

 than in Actinophrys sol, but have the same composition. They are quite 

 changeable in form; usually tapering and simple, they sometimes fork at an 

 acute angle. In the elongation of the body of the animal, the poles often 

 appear more or less abruptly tapering into one or several of the coarser 

 pseudopodal rays. Sometimes the rays become clavate or thickened as 

 they proceed outwardly, and rarely I have seen one or more divide in a 

 brush-like manner at the distal extremity. Commonly straight, they will 

 sometimes become quickly tortuous, especially in the act of retraction, and 

 sometimes they become beaded in appearance. Occasionally some of the 

 finer ones will form a little ball at the end, so as to resemble the pin-like 

 suctorial rays of Acineta. 



