BIOTIC ASSOCIATIONS OF COCKROACHES — ROTH & WILLIS 205 



papers, we concluded that Schwabe, in Hawaii, may well have been 

 working with the bisexual strain and possibly also with the partheno- 

 genetic strain; if this is true, then both parthenogenetic and bisexual 

 strains of Pycnoscelus surinamensis may serve as intermediate hosts 

 of the eyeworm. 



Experimental hosts. — Periplaneta americana, Antigua (Hutson, 



1943)- 



Pycnoscelus surinamensis, U.S.A. (Sanders, 1929) ; Australia 

 (Fielding, 1927, 1928a) ; Hawaii (Schwabe, 1951). 



Rictularia coloradensis Hall, 1916 



Natural hosts. — Parcoblatta pensylvanica and Parcoblatfa virginica, 

 U.S.A., Ohio (Oswald, 1958) : Of 49 M^ood roaches collected, one of 

 each species contained a single larva each. 



Experimental hosts. — Blatta orientalis, Blattella germanica, Parco- 

 blatta pensylvanica, Parcoblatta virginica, Periplaneta americana, and 

 Supella supellectilium, U.S.A. (Oswald, 1958) : The larvae under- 

 went normal development in all species of cockroaches except B. 

 orientalis and P. americana in which cysts developed that contained 

 a reddish-brown pigment ; larvae in such cysts were dead or dying. 

 Eggs of R. coloradensis hatched in the midgut of B. germanica and 

 first-stage larvae entered the hindgut epithelium within 24 hours. The 

 larvae underwent two molts within a cyst formed by tissues of the 

 host's gut, the second molt occurring during the twelfth or thirteenth 

 day. In Parcoblatta, cysts were found free in the body cavity as well 

 as attached to the hindgut. In B. germanica and 6*. supellectilium the 

 cysts remained attached to the hindgut. Usually over 20 cysts de- 

 veloped in each infected Parcoblatta; fewer than 10 per insect devel- 

 oped in the other species. Larvae became infective to the definitive 

 host, the white-footed mouse [Peromyscus leucopus noveboracensis 

 (Fischer)], as early as the tenth day. 



Family SPIRURIDAE 



* Agamospirura parahormeticae Pessoa and Correa, 1929 



Natural host. — Parahormetica bilobata, Brazil (Pessoa and Correa, 

 1929). 



* Gongylonema ingluvicola Ransom, 1904 



Experimental host. — Blattella germanica, U.S.A. (Cram, 1935). 



