296 



THE SPOROZOA 



40 species known, but not all named ; found in the gills, fins, scales, 

 kidney, spleen, etc., of various fishes, usually in the connective tissue 

 of these parts. The genus is divisible into three sections ; in the 

 first come the aberrant forms M. piriformis, Thel., of the tench (Tinea 

 tinea), and M. unicapsulatus, Gurley, from Labeo niloticus, which have 

 pear-shaped spores, each with a single polar capsule ; in the second are 

 M. dispar, The"!., from Cyprinus rutilus and Leuciscus rutilus, and M. 

 inaequalis, Gurley, from Pimelodus blochi and P. clarias, both with two 

 polar capsules of unequal size ; while in the third section are the very 

 numerous forms characterised by two polar capsules of equal size, the best 

 known being M. miilleri, Biitsch., the type-species (Fig. 99), from various 



FIG. 112. 



Spores of Henneguya psorospermica, Thel., 

 from the pike, a and d are seen lying with 

 the sutural plane horizontal ; 6 and c with 

 the sutural plane vertical, c is an abnormal 

 spore. 



Fio. 113. 



Spores of various Glugeidae, xloOO, after 

 Thelohan. a and 6, Pleistophora typicalis, 

 Gurley ; a in the fresh condition, b after 

 treatment with iodine water, causing ex- 

 trusion of the filament, c and d, Thelohania 

 octospora, Henneguy ; a fresh, 6 treated with 

 ether, e, Glugea depressa, Thel., fresh, f, 

 G. amta, Thel. 



fish (Squalius cephalus, Barbus barbus, Phoxinus laevis, Grenilabrus melops, 

 Thymallus vulgaris) ; M. ellipsoides, Thel., of the tench (Fig. 109); 

 M. pfeifferi, The"!., cause of the deadly barbel-disease ; and M. cyprini, 

 Don., from the carp. Genus 11. Henneguya, Thel., 1892. Spore with 

 a tail-like process, with two polar capsules (Fig. 112). Four species 

 are known, two of which infest sticklebacks (Gasterosteus aculeatus 

 and pungitius) ; a third occurs commonly, with several varieties, in 

 the pike and the perch. Genus 12. Hoferellus, Berg., 1898, nom. nov. 

 for Hoferia, Don., 1898. Spore of broad and compressed form, with 

 two tail-like processes at the posterior pole. One species, H. cyprini, 

 Don., associated commonly with Myxobolus cyprini in the disease of the 

 carp. 



SUB-ORDER II. CRYPTOCYSTES, Gurley ( = Microsporidia, Balbiani). 



