52 ILLINOIS BIOLOGICAL MONOGRAPHS [262 



tomerite subglobular to elongate, length twice the width. Slight con- 

 striction, if any, at septum. Protonierite as wide or wider than deuto- 

 merite at the septum. Deutomerite cylindrical, well rounded at poste- 

 rior end. Endocyte tranluscent. Nucleus visible in vivo, ellipsoidal, one 

 spherical karyosome. 



Cyst and spores unknown. 



Taken at Philadelphia and Wyncote, Pa., and Raleigh, N. C. Host: 

 Fo7itaria virginiensis (Drury) (Polydesmus virginiensis). Habitat: 

 Intestine. 



This species was described by Leidy (1863:238). 



Leger (1892:132) described a species, Amphorella pohjdesmi, from 

 the intestine of Polydesmus complanatus (L.). He created for the 

 species a new genus, characterized by the presence of a short circular 

 cup-like protomerite. 



Labbe (1899:20) united the A. polydesmi of Leger and G. polydes- 

 mi virginiensis of Leidy as one species and because Amphorella was in- 

 valid, called the genus Amphoroides and the species Amphoroides poly- 

 desmi (Leger). 



But the protomerite of G. polydesmi virginiensis does not coincide in 

 shape with that of the genus Amphoroides, for it is subglobose and bears 

 no indication of a cup-like depression which is characteristic of the latter 

 genus; therefore it must be placed elsewhere. The tliree following fac- 

 tors coincide with those of the genus Stenophora, viz: a) subglobose pro- 

 tomerite, b) relative length of protomerite as compared with total length, 

 c) solitary sporonts. The spores and the epimerite still remain undis- 

 covered and until they are found the generic determination is, of course, 

 not absolute. 



Crawley (1903:45-6) called the species G. polydesmivirginiensis 

 (Leidy), but in a later paper (1903a :640) he included it in a group of 

 doubtful forms, all of wiiich, however, he placed in the genus Gregarina. 



Ellis (1913b :274) erroneously attributes to Crawley the assignment 

 of the species name Amphoroides polydesmivirginiensis. It is Ellis him- 

 self at this point who names the species A. polydesmivirginiensis 

 (Leidy). He offers no explanation therefor. 



For the reasons given above, the species is now removed from the 

 genus Amphoroides and placed in the genus Stenophora, tlie name now 

 standing Stenophora polydesmi (Lankester) Watson. The trinomial of 

 Leidy was shortened to a binomial by Lankester and this binominal 

 must stand. 



This is a well defined species, having been found and drawn by 

 Crawley in 1903 and taken from the host in which it was originally 

 found. The writer has examined a half dozen specimens of this diplopod 

 taken at Urbana, without finding an instance of infection. 



