1919] 



Kofoid-Swezy: Lcidyopsis sphaerica 



101 



iu Leidyopsis is thus marked only iu its neuromotor system, while 

 the remaiuder of the body still shows a low degree of development. 

 Its mode of nutrition is holozoic, as shown by the food particles in 

 the eudoplasm, yet no cytostome or other organelles for food taking 

 are present. 



Shape and Size 



In size Leidyopsis sphaerica presents less variation than has been 

 found in the three other flagellates previously described from the 

 same habitat. This is probably due, however, to the paucity of our 



centrobleph. 

 . _ - has. gr. 



Fig. A. Diagrammatic figure of Lcidyopsis sphaerica gen. nov., sp. uov. Ecto^ 

 plasm drawn in sections to show structure of its different parts. 



Abbreviations: alv. I., alveolar layer; has. gr., basal granules; centrobleph., 

 centroblepharoplast ; ect., ectoplasm; end., endoplasm; /. 6., food bodies; fl., 

 flagella; long, my., longitudinal myonemes; n., nucleus; obi. /., oblique fibers; 

 oper., operculum; per., periplast; sur. rdg., surface ridges. X 400. 



material, as a larger number of individuals would present room for 

 greater variations. It is nearly spherical in shape, its length only 

 a few microns greater than its width, due to the cone-shaped pro- 

 jection of the anterior end of the body. The length varies from 

 165 to 190;a and the width 160 to 185/^. Figure 1 of plate 13 is that 

 of an individual 182/x in length and 176/i in breadth. These pro- 

 portions vary considerably, particularly in stained material where the 

 body becomes flattened and relative proportions almost entirely lost. 

 Measurements are of value only when made from the living organism. 

 The body is perfectly symmetrical in outline, a condition found 

 in only a few protozoans. The shape is that of a sjjhere with the 



