at various loci on the long axes of the tri- chomes. Motile strains possess peritrichous flagella. Anaerobic, although probably micro- aerophilic (see Simons, Zent. f. Bakt., I Abt., Orig., 88, 1922, 508 and 509; and Hoc- quette, Compt. rend. Soc. Biol., Paris, 113, 1933, 779). Habitat: Found in the alimentary tracts of various animals. FAMILY III. ARTHROMITACEAE PESHKOFF, 1940. (Jour. Gen. Biol. (Russian), /, 1940, 611 and 616.) Ar.thro.mi.ta'ce.ae. M.L. mas.n. Arthromitus type genus of the family; -aceae ending to denote a family; M.L. fem.pl.n. Arthromitaceae the Arthromitus family. Trichomes probably divided into cells although septa (protoplasmic?) disappear during sporulation. Disc-like nuclei alternate with thin protoplasmic segments (septa). Spores form in the distal ends of trichomes. Non-motile. The trichomes are attached by a spherical body in groups to the intestinal walls of insects, crustaceans and tadpoles. Genus I. Arthromitus Leidy, 1849. (Proc. Acad. Nat. Sci., Philadelphia, 4, 1849, 227.) Ar.thro.mi'tus. Gr. noun arthrus a joint; Gr. noun mitus a thread; M.L. mas.n. Arthro- mitus jointed thread. Characters as for the family. Although the descriptions are worded somewhat differently, there does not seem to be any essential difference between this and the following genus. The type species is Arthromit^is cristatus Leidy. 1. Arthromitus cristatus Leidy, 1849. (Proc. Acad. Nat. Sci., Phila., 4, 1849, 227; also see Jour. Acad. Nat. Sci., Phila., 8, 1881, 443.) cris.ta'tus. L. adj. cristatus crested. Cells short, cylindrical and uniform with no trace of interior structure, 0.6 by 2.75 microns. Trichomes delicate, straight or inflected, growing in tufts usually of mod- erate density, from minute, attached, yel- lowish, rounded or ovoid bodies. Breadth of trichome, 0.6 micron; length, 67 to 543 mi- crons. Source: Found in the intestines of the milliped (Julus marginatus) and the termite (Reticulitermes Jlavipes) . Also found on the mucous membrane of the small intestine of Julus marginatus, occasionally on the same surface at the commencement of the large intestine, on any part of the exterior sur- face of protozoa infesting these cavities and also on any part of the surface of Entero- bryus elegans. 2. Arthromitus intestinalis (Valentin, 1836) Peshkoff, 1940. {Hygrocrocis intes- tinalis Valentin, Repert. f. Anat. u. Phys., 1, 1836, 110; Peshkoff, Jour. Gen. Biol. (Rus- sian), 1, 1940, 597.) in.tes.ti.na'lis. L. pi. noun intestinae intestines; M.L. adj. intestinalis pertaining to the intestines. Cells are somewhat variable in size; how- ever, generally speaking, they are approxi- mately as wide as they are long. Trichomes are long, non-motile and grow indefinitely. In the spore regions of these trichomes there is a spore per cell; these sporogenous cells exhibit no hypertrophy. According to Leidy (Proc. Acad. Nat. Sci., Phila., 4, 1849, 227) these trichomes attach themselves to the intestinal wall by means of a sort of globu- lar, common holdfast. Source: Found in the intestine of the cockroach (Blatta orientalis). Habitat: Found in the intestines of cer- tain insects. 3. Arthromitus nitidus Leidy, 1852. (Smithsonian Contributions to Knowledge, 5, 1852, 35.)
