ON THE CLASSIFICATION OF THE MYXOSPORIDIA. 
413 
As a result of this analysis, the order Phcenocystes may be divided into the follow- 
ing families: 
CYSTODISCID2E fain. uov. 
Definition: Phcenocystes whose spores possess antero posterior and bilateral sym- 
metry; capsules in 2 groups, situated at the (anterior and posterior) ends; a bivalve 
shell, the plane of junction of whose valves is perpendicular to the longitudinal plane: 
condition of sporoplasm* * * § unknown; type (and only) genus Cystodiscu^Lutz. 
CYSTODISCUS Lutz, 1889. 
Centralbl. f. Bakt. u. Parasitenkde., v, p. 88. 
Definition: Characters those of the family; type, G. immersus Lutz. 
Cystodiscus immersus Lutz, 1889. 
Centralbl. f. Bakt. u. Parasitenkde., v, pp. 84-88; figs, separately and subsequently. 
Cystodiscus ? diploxys sp. nov. 
(Psorosperms of Pyralis viridana Balbiani 1867, Journ. Anat. et Physiol. Paris, p. 335 (foot- 
note), 1. 12, f. 10-12.) 
Spore : Parallel- sided fusiform ; ends symmetrically double convex-curved pointed ; 
plane of junction of valves coincident with the vertical plane; capsules 2 at each end, 
of equal size. 
Habitat: Tortrix viridana. 
MYXOBOLIDiE fain. nov. 
(Myxosporidiecef Perugia, 1891, Boll. Seientif. Pavia, xm, p. 23; “Myxobofijes ” Thflohan, 1892, 
Bull. Soo. philomat. Pafis, iv, pp. 173, 176.) 
Definition: Phcenocystes whose spores are destitute of antero posterior, but pos- 
sess bilateral, symmetry; f capsules in 1 group at the anterior end; a bivalve shell, the 
plane of junction of whose valve is parallel to the longitudinal plane; an iodinophile 
vacuole; type (and only) genus, Myxobolus Biitscldi. 
MYXOBOLUS Biitschli, 1882. 
Bronn’s Tkier-Reick, i, t. 38, f. 6-10; Myxosporidium § Perugia, 1891, Boll. Seientif. Pavia, xm, 
p. 23; Myxobolus et Myxosporidium Weltner, 1892, Sitzgsber. d. Gesellsch. Naturf. Freunde 
Berlin, pp. 34-35; Myxobolus et ffenneg u,ya\\ Thelohan, 1892, Bull. Soc. philomat. Paris, iv, 
pp. 176, 177. 
Definition: Characters those of the family; type M. mulleri Butschli. 
* Sporoplasm. Protoplasm of the spore. 
II propose Myxosporidium Perugia (synonym for Myxobolus Butschli) as the type genus of the Fam. 
Myxosporidiece Perugia. 
1 Except species which have suffered reduction of characters (Myxobolus unicapsulatus sp. nov., M. 
piriformis Tliel.). 
§ I propose M. merlucii Per. as the type species of this genus. 
|| I propose R. psorospermica Thel. as the generic type. No valid generic distinction seems possi- 
ble between the uutailed and the tailed forms, for which latter Thelohan proposed Henneguya. Apart 
from the absence or presence of a tail (both of which conditions may, according to good observers, 
occur in the same species; cf. Weltner, Sitzgsber. Ges. Naturf. Freunde Berlin, 1892, pp. 28-36) the 
only character relied upon for their separation is the coustane y of 2 capsules in the tailed forms, but 
this is also the typical number for Myxobolus aud the presence of two exceptional species does not 
militate against the rule. 
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