_Ref._--Siebold, Naturg. wirbelloser Thiere (1839) _fide_ Stein; Stein, Organismus d. Infusions-thiere, Bd. II., p. 345 (1867); Bütschli, Zeits. f. wiss. Zool., Bd. XXX., p. 273, pl. xv. (1878); Leidy, Proc. Acad. N. S. Phil., Oct. 7th, 1879, and Freshwater Rhizopods of N. America, p. 300 (1879). _Gregarina (Clepsidrina) Blattarum_, Sieb. GREGARINIDA. Encysted in chylific stomach and gizzard; free in large intestine. _Ref._--Siebold, Naturg. wirbelloser Thiere, pp. 56, 71 (1839); Stein, Müll. Arch., 1848, p. 182, pl. ix., figs. 38, 39; Leidy, Trans. Amer. Phil. Soc., Vol. X., p. 239 (1852); Bütschli, Zeits. f. wiss. Zool., Bd. XXI., p. 254 (1871), and Bd. XXXV., p. 384 (1881); Schneider, Grégarines des Invertébrés, p. 92, pl. xvii., figs. 11, 12 (1876). _Nyctotherus ovalis_, Leidy. INFUSORIA. Small and large intestines. _Ref._--Leidy, Trans. Amer. Phil. Soc., Vol. X., p. 244, pl. xi. (1852). _Plagiotoma (Bursaria) blattarum_, Stein. INFUSORIA. Rectum. _Ref._--Stein, Sitzb. d. königl. Böhm. Ges., 1860, pp. 49, 50. _Lophomonas Blattarum_, Stein. INFUSORIA. Rectum. _Ref._--Stein (loc. cit.); Bütschli, Zeits. f. wiss. Zool., Bd. XXX., p. 258, plates xiii., xv. (1878). _L. striata_, Bütschli. INFUSORIA. Rectum. _Ref._--Bütschli, Zeits. f. wiss. Zool., Bd. XXX., p. 261, plates xiii., xv. (1878). _Gordius_, sp. NEMATELMINTHA. Specimens in the Museum at Hamburg, from Venezuela. Obtained from some species of Cockroach. _Oxyuris Diesingi_, Ham. NEMATELMINTHA. Rectum, frequent. _Ref._--Hammerschmidt, Isis, 1838; Bütschli, Zeits. f. wiss. Zool., Bd. XXI., p. 252, pl. xxi. (1871). _O. Blattæ orientalis_, Ham. NEMATELMINTHA. Rectum (much rarer than _O. Diesingi_). _Ref._--Hammerschmidt (_loc. cit._); Bütschli, Zeits. f. wiss. Zool., Bd. XXI., p. 252, pl. xxii. (1871). Other species of _Oxyuris_ are said to occur in the same situation, _e.g._, _O. gracilis_ and _O. appendiculata_ (Leidy, Proc. Acad. N. S. Phil., Oct. 7th, 1879), and _O. macroura_ (Radkewisch, quoted by Van Beneden in Animal Parasites, Engl. trans., p. 248). _Filaria rhytipleurites._ NEMATELMINTHA. Encysted in the fat-body of the Cockroach; sexual state in the alimentary canal of the Rat. _Spiroptera obtusa_ is similarly shared by the Meal-worm (larva of _Tenebrio molitor_) and the Mouse. _Ref._--Galeb, Compt. Rend., July 8th, 1878. _Acarus_, sp. ARACHNIDA. Found by Cornelius upon the sexual organs of a male Cockroach. _Ref._--Cornelius, Beitr. zur nähern Kenntniss von _Periplaneta orientalis_, p. 35, fig. 23 (1853). _Evania appendigaster_, L. INSECTA (_Hymenoptera_).