66 ILLINOIS BIOLOGICAL MONOGRAPHS [304 



Vegetative form: Polymorphous; generally club-shape, pseudopodia 

 localized at the broad end; the other end cylindrical or terminating in a 

 sharp point. Some other different forms. Pseudopodia, always localized, 

 lobose pointed at the extremities. Ectoplasm hyahne and thin. Endo- 

 plasm contains fat globules and particular elements, mostly large refractive 

 globules, which seem to disappear in the sporulating individuals. Dimen- 

 sions (maximum): length 35 to 40/i, breadth 12 to 15)U, pseudopodia about 

 10/x long. Disporous. 



Spore: Arch form. Shell valves equal. Sporoplasm occupies the 

 extracapsular cavity of the spore. The length varies rather considerably 

 according to the development of the lateral processes, which are occasionally 

 acuminated or very short. Often extremities are rounded. Dimensions 

 (Thelohan) ; breadth 20 to 30jLt, sutural diameter 5 to 8^, Parisi's measure- 

 ments: breadth 25 to Sl/n, sutural diameter 5.5 to 6/i, length of polar 

 capsules 3.5 to 4/i, length of polar filaments 25^t. 



Remarks: The writer agrees with Parisi in eliminating Labbe's two 

 subspecies (1899:90), as they are too arbitrary. 



CERATOMYXA SPHAERULOSA Thelohan 



Habitat: Gall-bladder of Mustelus canis Mitch. {M. vulgaris), Galeus 

 galeus L. {G. canis), Clupea harengus, Scullium canicula Cuv.; St-Valery- 

 en-Caux, Roscoff, Bergen, Monaco (May). 



Vegetative form: Form more or less definite among the adults. Gen- 

 erally elongated. Both ends shghtly attenuated. Wide in the middle part 

 of the body. Lobose pseudopodia at one of the extremities. Others 

 more massive or more or less regularly spherical, in which case the pseu- 

 dopodia are formed from the whole surface. Spherical form does not 

 exceed 50 to 60m in diameter. Other forms 90 to 100/x by 30 to 40^ (largest). 

 Young forms colorless and are more variable than the adults. Protoplasm 

 homogeneous and finely granular. Adult form, on the contrary, yellowish 

 or greenish yellow. The endoplasm is filled with small (5/i in diameter) 

 spheres, in the centre of which 5 to 6 small granules, yellowish brown or 

 greenish in color, are present. Disporous. 



Spore: Remarkably large. Polar filament can be seen in vivo (easily 

 extruded by KOH, ether, etc.) Sporoplasm occupies one of the shell-valves, 

 while a small mass of very pale looking substance is seen in the other. 

 Dimensions: sutural diameter 10 to 12/i, breadth 90 to 100m, subspherical 

 polar capsule 6 to 7 by 5m, sporoplasm 12 to 15 by 8 to 9m. 



