102 ILLINOIS BIOLOGICAL MONOGRAPHS [312 



in vivo and not seen. Cysts spherical, 250/x. in average diameter. Spore 

 ducts 2 to 5, of maximum length 1000/A. Spore barrels shaped, 4.5 by 



Taken at Haverford and Philadelphia, Pa., Beach Haven, N. J., 

 Douglas Lake, Mich., Urbana, 111., Oyster Bay, L. I. Hosts: Gryllus 

 abbreviatus Serv. (Acheta abbreviata); G. americanus Blatch. Habitat: 

 Intestine. 



Leidy's drawing of the species (1853), my figure 191, represents the 

 same gregarine as that described by later writers. But later drawings 

 from Leidy's unpublished manuscript, Crawley's 1903 paper (PI. Ill, 

 Pigs. 34, 35), show two distinctly different species, one associative and 

 the other not. Crawley confused the two in his description, under the 

 name Gregarina achetaeabbreviatae. In 1907 he described two distinct 

 species, however, one the Gregarina achetaeabbreviatae of Leidy and a 

 new Stenophora erratica, for the solitary species. The latter I have 

 transferred to a new genus Leidyana. For description, see under L. 

 erratica. 



Ellis found this species at Douglas Lake, Mich., and I have found 

 it from material taken at Haverford, Pa., Urbana, 111., and Oyster 

 Bay, L. L 



Diesing changed the name of Leidy's species to Gregarina oviceps 

 without giving explanation therefor and since this is the oldest binom- 

 ial name used, the species must bear this name. 



GREGARINA MACROCBPHALA (Schneider) Labbe 



1875 Clepsidrina macrocephala Schneider 1875 :674 



1882 Clepsidrina macrocephala Schneider 1882:442 



1887 Clepsidrina macrocephala Schneider 1887 :73 



1895 Clepsidrina sp. Cuenot 1895 -.321 



1897 Clepsidrina gryllorum Cuenot 1897 :54 



1899 Gregarina macrocephala Labbe 1899 :10 



Gregarina : Sporonts biassociative. 



The following synopsis refers to the cephalont only, there being 

 no available description of the sporont. 



Ratio length protomerite : total length primite :: 1 : 5; width 

 protomerite : width deutomerite :: 1 : 1.2. Protomerite rounded 

 laterally, as wide as high. Constriction at septum. Epimerite super- 

 imposed upon protomerite on a short stout neck. Epimerite a large 

 hyaline ovoidal body a little longer than the protomerite of the cepha- 

 lont. Deutomerite elongate cylindrical, tapering suddenly to a sharp 



