50 ILLINOIS BIOLOGICAL MONOGRAPHS [260 



striations in the epicyte and it is interesting to note that he discovered 

 them during his first observations on the gregarines. 



Leidy renamed the species four years later from the host in which 

 it was found. 



Lankester (1863:94), in a classification of the gregarines, grouped 

 three of Leidy 's forms : G. larvata, G. juli marginaii, and G. juli pusilli, 

 together with Gregarina juli Frantz. under the name of the latter, ap- 

 parently because they were all parasites and the only known parasites 

 of the same diplopod. 



Schneider (1875:585) disregarding the rule of priority united Gre- 

 garina juli marginati and a species which he discovered under the name 

 Stenocephalus juli (Leidy). His remarks are as follows: 



"Cette espece est commune et me parait etre identique a celle decrite par 

 Leidy sous le nom de Gregarina juli marginati. Dans ce cas elle serait probable- 

 ment repandue chez les differentes especes du genre Julus, puisqui'on la con- 

 naitrait deja chez trois d'entre elles. . . . L'espece est legerment polymorphe 

 elle est tantot tres-allongee et relativement etroite, tantot remarquablement mass- 

 ive; mais son protomerite demeure toujours identique a lui-meme et sufifit ample- 

 ment au diagnostic." 



Leidy gave no measurements of his species and Schneider based the 

 identity of the two forms on the similarity of Leidy 's figures with his ma- 

 terial . It is true that in general shape the two are very similar but the 

 protomerites differ slightly and the color differs markedly. Leidy 's spe- 

 cies is white ; Schneider 's yellow to yellow-orange. Because of these dis- 

 similarities, the two forms should be separated. 



Labbe (1899:15) changed the name of the genus Stenocephalus of 

 Schneider to Stenophora. 



Crawley (1903a; 634) did not consider the two species identical. 

 His words are as follows : 



"There is a good deal of confusion regarding the gregarines occurring in 

 the Diplopod family Julidae. These gregarines all bear a certain amount of 

 resemblance to one another, and it has been usual to relegate all of them to the 

 species ::>tenophora juli Frantz. Leger and Duboscq (1903) have recently shown 

 that such a procedure is not warranted for the fauna of Corsica and the case is 

 certainly the same for that of the eastern United States. The Julidae of this 

 region are infected with certainly two and possibly three species of Stenophora, 

 while the classic S. juli apparently does not occur." 



Leger and Duboscq (1904:361-2) take up the same discussion in 

 their history of the Stenophoridae as follows : 



"Leidy fit connaitre une Gregarine assez particuliere, parasite de I'intestin 

 de lulus marginatus Say. II I'appela d'abord (1851) Gregarina larvata, puis 

 changea son nom en celui de Gregarina iuli marginati dans un travail posterieur 

 (1853) ou il decrit une autre Gregarine, G. iuli pusilli, parasite d'un petit iule . . . 

 qui n'est pas lulus pusillus Leach. 



