Page:Bergey's manual of determinative bacteriology.djvu/301

 which bits of the exoskeleton of marine crabs were added. No growth took phice on agar media so that no pure cultures were obtained. Cultures were incubated at room temperature in the dark. Further information regarding the organisms belonging to the genera of this family is greatly needed. Key to the genera of family Pasteuriaceae. I. Stalks lacking; cells sessile. Genus I. Pasteuria, p. 279. II. Stalks long and slender, often in whorls. Genus II. BlastocauUs, p. 279. Genus I. Pasteuria Metchnikoff, 1888. (Ann. Inst. Past., 2, 1888, 166.) Pas.teu'ri.a. M.L. gen.n. Pasteuria of Pasteur; named for Louis Pasteur, the French scientist. Pear-shaped cells attached to each other or to a firm substrate by holdfasts secreted at the narrow end. Multiplication is by longitudinal fission and by budding of spherical or ovoid cells at the free end. Non-motile. Non -pigmented. Parasitic on fresh-water Crustacea. The type species is Pasteuria ramosa Metchnikoff. 1. Pasteuria ramosa Metchnikoff, 1888. found by Henrici and Johnson {ibid., 71 (Ann. Inst. Past., 2, 1888, 166.) and 77) in Lake Alexander, Minnesota; ra.mo'sa. L. adj. ramosMS much-branched, these appeared frequently on glass slides Cells 1 to 2 by 4 to 5 microns. Non-motile, submerged in the lake water; they produced Non-pigmented. Cells grow attached to reproductive bodies apparently by budding each other in cauliflower-like masses, multi- rather than by an endogenous formation, plying by longitudinal fission or by intra- Photomicrographs are shown in Henrici cellular bodies which are extruded as buds, and Johnson {ibid., 93, plate 3, fig. 4). ZoBell apparentlj^ reproductive in nature; at times and Allen (Proc. Soc. Exp. Biol, and Med., these colonies break up into smaller ones 30, 1933, 1409) and ZoBell and Upham (Bull, and continue to separate until all of the Scripps Inst. Oceanography, LaJolla, Cal- individual cells are liberated. Cells and ifornia, 5, 1944, 243) used a submerged- methods of reproduction resemble those slide technique in sea water and found simi- of Chamaesiphon, a genus of blue-green lar bacteria. algae (Henrici and Johnson, Jour. Bact., Source: From the body cavities of Daph- 30, 1935, 71). Gram stain not recorded. nia pulex and D. magna. Related species: Free-living organisms Habitat: Parasitic on fresh-water crus- which resembled Pasteuria ramosa were tacea so far as known. Genus II. Blastocaulis Henrici and Johnson, 1935. (Jour. Bact., 30, 1935, 84.) Blas.to.cau'lis. Gr. noun blastus a sprout, shoot, bud; Gr. noun caulis a stalk; M.L. fem.n. Blastocaulis a bud stalk. Pear-shaped or globular cells attached to a firm substrate by long, slender stalks with a holdfast at the base; stalks may occur singly or may arise in clusters from a common hold- fast. Not cultivable on artificial media. Found on firm substrates in fresh water. The type species is Blastocaulis sphaerica Henrici and Johnson. 1. Blastocaulis sphaerica Henrici and sphae'ri.ca. Gr. adj. sphaericus spherical. Johnson, 1935. (Jour. Bact., 30, 1935, 84.) Cells spherical, 1 to 2 microns in diameter.