106 ILLINOIS BIOLOGICAL MONOGRAPHS [316 



Endocyte very dense and brownish yellow in deutomerite, tan in pro- 

 tomerite. Epimerite a small spherical hyaline knob. 



Cysts yellow orange, 300/* in average diameter, spore ducts short, 

 ten or more in number. Spores extruded in chains, barrel shaped, 

 5 by 8/i. 



Taken at Wyncote, Pa. ; Douglas Lake, Mich. ; Lincoln, Neb. ; Colo- 

 rado Springs, Colo. ; Boulder, Colo. ; Urbana, 111. ; and Oyster Bay, L. I. 



Hosts Melanoplus femoratus (Burm.) ; M. luridis (Dodge) ; M. 

 femur-rubrum (de Geer) ; M. atlantis (Riley) (M. atlantis); M. differ- 

 entialis (Uhler) ; M. coloradensis ? ; M. angustipennis (Dodge) ; En- 

 coptolophus sordidis (Burm.); Schist ocerca americana Burm.; M. bi- 

 vitattus (Say); Hesperotettix pratensis Scudder; Brachystola magna 

 Giard. Location: Intestine and caeca. 



This species was first described by Hall as Hirmocystis rigida. He 

 mentioned dehiscence of the cysts by simple rupture, and he saw neither 

 the spores nor the epimerite. The only character in common with the 

 genus Hirmocystis was the simple rupture of the cysts, and this char- 

 acter is possessed by some thirty genera. 



Crawley (1907) published an article two months later describing 

 a new species, Gregarina melanopli, which proved to be the same species. 

 He found that dehiscence occurred by means of numerous spore ducts. 

 The epimerite was still unknown. 



Ellis changed the name of the species to Gregarina rigida (Hall). 



I have taken parasites of this species from various Acrididae in 

 material from Colorado Springs, Lincoln, and Urbana. In three in- 

 stances specimens were recovered from M . femur-rubrum at Oyster Bay, 

 L. I. (Fig. 271). Although hundreds of grasshoppers have been exam- 

 ined at the latter place, infection has been found but these few times, 

 and then very few parasites were present. Cysts have developed, all 

 with numerous long spore ducts. Typical spores were extruded. 



GREGARINA KINGI Crawley 

 [Figure 193] 



1907 Gregarina Ungi Crawley 1907:221-3 



1913 Gigaductus kingi EUis 1913b:271 



Gregarina: Sporonts biassociative, rather stout bodied. Maximum 

 length of associations 350/t. Sporont measurements not given. Ratio 

 length protomerite : total length : : 1 : 3 ; width protomerite : width 

 deutomerite ::!:!. Protomerite saddle-shaped, i.e. broadly dilated 

 and nearly flattened apically, with deep constriction just below middle, 



