II. Non-motile trichomes. Found in the buccal cavities of vertebrates. Genus III. Simonsiella, p. 833. Genus I. Caryophanon Peshkoff, 1940. (Jour. Gen. Biol. (Russian), 1, 1940, 611 and 616.) Ca.ry.o'pha.non. Gr. nouncaryum nut, kernel, nucleus; Gr. adj. phanus bright, conspicu- ous; M.L. neut.n. Caryophanon that which has a conspicuous nucleus. During active growth, the large filamentous and bacillary structures are essentially tri- chomes containing packed, discoid, protoplasmic units separated by internal crosswalls. The unstained trichome has the appearance of alternating light and dark bands. Trichomes may form long, unsheathed filaments. Spherical, single-celled structures are commonly seen. Kelley (Thesis, Ohio State Univ., 1952) states that the internal crosswalls are complete and that the chromatinic material is either disc-shaped or spherical depending upon the shape of the cell. Found in fresh cow dung. The type species is Caryophanon latum Peshkoff. 1. Caryophanon latum Peshkoff, 1940. (Compt. rend. (Doklady) Acad. Sci., U.R.S.S., Nouvelle S^r. 25, 1939, 244; Jour. Gen. Biol. (Russian), 1, 1940, 527; Micro- biology (Russian), 15, 1946, 189.) la'tum. L. adj. latus broad. Additional descriptive material taken from Pringsheim and Robinow (Jour. Gen. Microbiol. (London), 1, 1947, 267), Weeks and Kelley (Bact. Proc, Soc. Amer. Bact., 1951, 39) and Kelley (Thesis, Ohio State University, 1952). Trichomes measure 3 or more microns by 6 to 20 microns. The bacillary unit or tri- chome shows alternating light and dark bands completely traversing the structure. The ends of the trichomes are rounded. The light bands seen in the unstained, fresh, wet mounts are the basic, discoid protoplasmic units; the dark bands are internal cross- walls. Each protoplasmic unit may extend from 0.6 to 1.8 microns along the longitu- dinal axis of the trichome, the crosswalls occupying from 0.15 to 0.3 micron of the same dimension. The number of discoid protoplasmic units per trichome varies from 4 to 22 depending on the length and age of the trichome and upon the cultural condi- tions. Trichomes divide transversely. Older populations (24 hours to 4 days), or cultures growing under unfavorable conditions, con- tain, or show exclusively, spherical cells 3 microns in diameter, each containing a single protoplasmic unit. Nuclear structures of discoid cells are disc-shaped, of spherical cells, rounded (Kelley). Trichomes may form unsheathed filaments up to 200 microns in length. The diameters of trichomes and spherical cells may lessen as much as 50 per cent on cultivation for a j'ear or more in the laboratory. Motility: Trichomes show active motility even when they grow out into long filaments. The spherical units are less active. Peri- trichous flagella. Agar colonies : Colonies are 1 to 2 mm in diameter with entire or slightly undulating margins. Original isolations usually develop smooth colonies. Rough colonies predom- inate during laboratory cultivation. Long filaments tend to occur in the rough colo- nies; short, individual trichomes occur in the smooth colonies. The colonies appear in 6 to 8 hours on peptone-yeast extract- sodium acetate agar (Pringsheim and Rob- inow). Irregular giant' forms may develop from older cultures (Peshkoff). Rapid growth on peptone-yeast extract- sodium acetate agar, pH 7.6 to 7.8. Also on cow dung extract agar, pH 7.8 to 8.0. Growth at pH 7.0 produces spherical units. No growth on nutrient agar (Pringsheim and Robinow) ; poor growth (Kelley) . Poor growth in liquid media; added col- loids result in the growth of long filaments. The organism survives for long periods in liquid media. Aerobic. Not known to be pathogenic. Source: Isolated from 20 to 30 per cent of samples of fresh cow dung. Isolated at least 20 times in Moscow (U.R.S.S.) and its vicinity by Peshkoff. Isolated and culti-
