409] STUDIES ON MYXOSPORIDIA— KUDO 171 



HENNEGUYA BRACHYURA Ward 

 [Figs. 650 to 653] 

 1919 Henneguya brachyura Ward 1919 : 57 



Habitat: In the cartilageous fin ray of the caudal fin of Notropis 

 anogenus; Put-in-Bay, Lake Erie (August). The species was found 

 encysted in the same fish which was heavily infected by Myxobolus aureatus. 



Vegetative form: Cysts rounded with slightly irregular contour im- 

 bedded in the fin ray. The size varies from 160/i in diameter up to 360/i by 

 240^1. No particular cyst membrane could be recognized. The differen- 

 tiation of the protoplasm into ectoplasm and endoplasm is distinct. The 

 ectoplasm covering the entire surface of the parasite as a layer 4 to 6/^ 

 thick, shows structure of a very finely granular nature. The endoplasm 

 coarsely alveolar, is filled with mature spores in the central portion, while 

 numerous nuclei and young spores in various developmental stages are 

 present at the peripheral portion. Polysporous. 



Spore: Rounded oval in front view; spindle shape with symmetrically 

 built valves in profile. Shell rather thick. Sutural ridge fairly well 

 marked; sutural edge exhibiting a variable number of folds (8 to 10). 

 Two pyriform polar capsules are usually of the same size and form. The 

 tail is a single process, usually more or less bent or irregularly curved, 

 very rarely being straight. In general, it is sinuous with two or three 

 shallow curves and is rather short, tapering gradually to a point. In 

 young spores which are less deeply stained by any stain, various develop- 

 mental stages of the tail are reasily recognized. Giemsa solution stains 

 the shell proper in clear blue, while the tail takes on a beautiful pink 

 color, a distinct difference in affinity for dyes between the material in the 

 tail and the shell. It seems probable that the tail of this type is entirely 

 different in its development from that of the ordinary bifurcated type. 

 Dimensions in section: length 10 to 11.5At, breadth 8 to 8.75iu, thickness 

 4 to Sfi, polar capsules 3 to 4jLt by 2fj., length of the tail up to 17 ix. 



HENNEGUYA SALMINICOLA Ward 



[Figs. 654 to 656] 



1914 ?Henneguya zschokkei Zschokke and Heitz 1914 : 200-201 



1919 Henneguya salminicola Ward 1919 : 59 



Habitat: In the sub-dermal tissue of Onchorhynchus keta and 0. kisutch 

 (Zschokke and Heitz, Kamtschatka) and in the connective tissue in body 

 muscles of Oncorhynchus keta, Stickeen River, Alaska (Ward, September). 

 The last named author undertook a careful examination of a part of the 

 infected tissue preserved in formol. The species forms conspicuous cysts 

 in the muscle from the sub-peritoneal to the sub-dermal connective tissue, 

 tho all are sub-peritoneal in position. 



