SPECIAL MORPHOLOGY AND TAXONOMY OF SPOROZOA 439 



13. Genus Dobellia, Ikeda (1914). Parasite of the gut of Sipunculidse 

 {Petalostoma minutum). 



Family 2. Eimeriidse, Leger. The forms included here, generally known 

 as the Coccidia, differ from the Adeleidse in having flagellated microgametes 

 and typical fertilization without pseudoconjugation of gametocytes. 

 Sporoblasts encapsulated for the most part. We follow Doflein in grouping 

 the many genera in ten sub-families as follows. 



Sub-family 1. Cryptosporinae, Leger. The single genus and species of 

 this group forms one of the interesting exceptions to the usual mtracellular 

 habitat of Coccidia. Like gregarines, it is a lumen-dwelling parasite of the 

 peptic glands of the mouse. Sporoblasts are either absent or the sporo- 

 cyst may be interpreted as forming one sporoblast with its capsule closely 

 applied to the sporocyst membrane, four sporozoites. The sporozoites 

 may develop in the same host thus leading to autoinfection. 



1. Genus Cryptosporidium, Tyzzer (1908). Small forms in the stomach 



glands of the mouse. 



Sub-family 2. Cyclosporinse, A. Sclm. The single genus included here 

 is characterized by the small number of reproductive bodies formed as a 

 result of fertilization. The agametes are said to be sexually differentiated 

 (Schaudinn), the zygote forms two sporoblasts each with two sporozoites. 



2. Genus Cyclospora, A. Sclm. The best known species is C. caryolijtica, 

 Schn., a nuclear parasite of the intestinal epithelium of the ground mole. 



Sub-family 3. Caryosporinae, Leger. The zygote forms only one sporo- 

 blast with eight sporozoites. 



3. Genus Caryospora, Leger (1904). Sporocyst a thick yellow membrane 



with a knot-like thickening at one point; sporoblast slightly pointed 

 at one end, intestinal epithelium of the asp, Viperia aspis L. 



4. Genus Pfeifferinella, Wasielewski (1904). The sporoblast has eight 



sporozoites and a conspicuous granular residual mass; parasitic in 

 snails Planorbis and Succinia. 



Sub-famUy 4. Isosporinae, Leger (1911). The zygote forms two sporo- 

 blasts each of which has four sporozoites in capsules. 



5. Genus Isospora, A. Sclm. (1881). Many different species have been 



described some of which may turn out to be new genera when the 

 full life history is known; parasites in widely different animal groups, 

 slugs (/. rara, A. Schn.), cats and dogs and possibly man {L bigemina, 

 Stiles); birds (/. lacazei, Labbe), and lizards (/. mesnili, Sergent). 



Sub-family 5. Eimerinae, Leger (1911). The zygote forms four sporo- 

 blasts each with two sporozoites (see typical life history p. 418). Aga- 

 metes without sexual dimorphism. Many species varying in minor details 

 but described by earlier observers as distinct genera which were brought 

 together by Ltihe as sub-genera of the genus Eimeria, A. Schn. (Coccidium, 

 Leuckart). 



6. Genus Eimeria, A. Schn. (1875). Types of the different sub-genera are 



given below with the sub-genus name in brackets, 

 (a) Eimeria {Goussia, Labbe), Schaudinn (1900). Memljrane of sporo- 

 cyst formed after fertilization; sporoblasts without the unex- 

 plained phase known as the "pyramid stage;" sporoblasts spher- 

 ical or oval with two valves which open in the gut of a new host; 

 parasites of fish (Labbe) and of centipedes (Schaudinn). (See 

 Fig. 178, p. 419.) 



