H/EMOSPORIDIA. 



61 



Tribe 2. Oligosporea. Cyst produces but few spores. Gydosporo Schn., 

 intest. epithelium of Glomeris, and the cat. Coccidium Leuck., in each of the 

 four spores only two falciform bodies ; in cells of the intestine and liver of 

 mammals, birds, reptiles, amphibia, and fishes ; C. oviformc Leuck. (Fig. 46), 

 epithelium of bile-duct and intestine of rabbit.* 



Tribe 3. Polysporea. With many spores. Klossia Schn., about sixty spores 

 each with four to six falc. bodies ; kidney Helix, Succinea, and Neretina ; 

 Minchinia Labbe, spores with two long filaments, in liver and connective tissue 

 of Chiton ; Barroussia, Schn., each spore with one falc. body ; Adelea Schn., in 

 intestinal epithelium of Lithobius forficatus. 



Order 3. H.EMOSPORIDIA. 



Minute intracellular parasite* 

 /rhich mainly infest, the corpus- a 



des of the blood. The spores 

 are naked and do not sub-divide. 



The Hcemosporidia, like the 

 Coccidiidea, never become so 

 large as to outgrow their cell- 

 host ; but they differ from 

 them in possessing naked spores. 

 Moreover the spores do not 

 sub-divide, but become directly 

 transformed into the young 

 forms, f It is not known how 

 they leave their host or how 

 they enter new hosts. 



Sub-order 1. DREPANIDIIDIA. 



The Drepanidiidia infest the blood-corpuscles and are found in Amphibia, 

 Reptilia, and Aves. They have not yet been found in fishes and mammals, 

 or in invertebrates. They were discovered by Ray LankesterJ in the frog. 



They are small uninucleated gregarine-like creatures which infest the red 

 blood-corpuscles (rarely the white blood-corpuscles and cells of spleen, liver, 

 and kidney) of their host. They cause the destruction of their cell-host, from 

 which they pass to live for a time freely in the blood. They then enter 

 another blood-corpuscle, secrete a cyst-wall, and break up into elongated oval 



* This forms an exogenous cyst, and it is a question how the rabbit becomes 

 infested with the innumerable coccidia which are present in acute coccidiosis. 

 It has been suggested that these coccidia reproduce in two ways the one by 

 exogenous sporulation as described in the text, and the other endogenously 

 in the cell-host by the direct breaking up of the coccidium into numerous 

 falciform bodies without the formation of spores, or by its simple division. 



t This statement perhaps requires qualification, for in some of the Acysto- 

 sporidia the so-called two-spored forms the nucleus of the form about to 

 sporulate divides into two, and gives rise to two centres of spore-formation. 

 (See below.) 



J Vide Quart. J. Mic. Sci., xi., 1871, and ibid., vol. xxii., 1882. 



FIG. 47. Danilewskya lacazei from the lizard, 

 a, three free forms with gregarine-like 

 appearance, fresh ; b, after treatment with 

 gold -chloride and Iwmatoxylin, showing 

 myocyte-fibrilke. 



