diseases of the type known as piroplasmosis. Babesia hominis 

 cause of "spotted fever" of man in Montana and Idaho. 



Order SARCOSPORIDIA 



Sporozoa found in or between the muscle-cells of vertebrates, 

 appearing as whitish, elongate-ovoid bodies. Great sac-like spore 

 cases, with double membranes, are formed. Take as a type. 



Sarcocystis miescheriana — Trophozoites occur commonly and 

 in great abundance in the muscles of hogs. Large, .6 or even 2-3mm. 

 in length, and sometimes visible to naked eye as greyish points. Wall 

 of a thick cuticle, transversely striated. Content, even in very early 

 stages granular from 'presence of great numbers of rounded "pan- 

 sporoblasts." The content of pansporoblasts divides to form finely 

 granular, pale sporoblasts, in each of which develops a spore. Method 

 of transfer from host to host unknown. Effect on host disputed but 

 where they occur so abundantly they must cause injury. Evidence 

 that there is an active poison secreted by the parasite itself. Laveran 

 and Mesnil claim to have isolated such a toxin, which they call sarco- 

 cystin, from Sarcocystis tenella, of the sheep. 



Order MYXOSPORIDIA 



Parasites of cold blooded animals, especially known as causing 

 serious epidemics among fish and in silk worms. Often called 

 psorosperms. Characterized by facts that the trophozoite is amoe- 

 boid; spore formation commences at an early stage and proceeds 

 continuously during the growth of the trophozoite; spores are pro- 

 duced within the protoplasm of the trophozoite, and each spore 

 always possesses one or more very distinctive structures known as 

 "polar capsules" — Lankester, '03. 



Nosema bombycis — The cause of "pebrine" or silkworm disease 

 which, until the work of Balbiani and of Pasteur, threatened to wipe 

 out the silk industry of France. 



Form — In tissues of host as a microscopic corpuscle enclosing 

 numbers of spherical sporoblasts from which develop many sporozo- 

 ites. Spores oval, 3/i long by LBfi. wide, characterized by the peculiar 

 "polar-capsule" and by a polar filament which is rendered visible by 

 the action of reagents. 



