FAMILY: NOSEMATID^ 



741 



polar capsule, and the other becomes the nucleus of the infective amoeboid 

 form or sporozoite, which escapes from the spore when it is taken into the 

 intestine of a new host. The spores are so minute and the capsule so 

 thick that the details of the development are exceedingly difficult to follow. 

 Another form, Nosema apis Zander, 1909, with spores measuring 1-6 to 6-4 

 by 2-5 to 3-4 microns, is supposed to be the cause of bee disease (Fig. 30), 



y^'^J^3K%^'' 



'"^^^■'-v-5-'fi»U»''^i' 



Fig. 314. — Nosema honibycis : Developmental Stages and Spoke Formation in 

 Intestinal Epithelial Cells of Silkworm {xca. 2.000). (After Stempell, 1909.) 



while N. frenzelincB Leger and Duboscq, 1909, parasitizes a gregarine 

 {Frenzelina conformis), which is itself parasitic in the crab, Pachygrctjjsus 

 marmoratus. 



Genus: Gurleya Dofiein, 1897. 



The members of this genus have elongate spores, which are broader 

 at one end than at the other. 



Gurleya francottei Leger and Duboscq, 1909. — This organism is 

 parasitic in the epithelium of larvae of Ptychoptera contaminata. The 

 pansporoblast gives rise to four spores, which are radially arranged 

 (Fig. 315). 



Genus : Thelohania Henneguy, 1892. 



The members of this genus occur as minute parasites in the cytoplasm 

 of cells of aquatic invertebrates. There is little tendency to the produc- 

 tion of multinucleate plasmodia. Multiplication is usually by binary 



