little; Gr. adj. meiabolus changeable; M.L. adj. pauro7netabolus little changeable, prob- ably intended to mean producing little change. Rods, 0.5 to 0.8 bj' 1.0 to 2.5 microns, oc- curring singly, in pairs and in masses. Meta- chromatic granules present. Non-motile. Gram-positive. Gelatin stab: Slow liquefaction at surface. Agar colonies: White to gra}^, entire, cir- cular, small, dry, somewhat granular. Agar slant: Filiform to arborescent, thick, granular growth. Broth: Abundant, granular sediment but no turbidity. Pellicle. Litmus milk: Alkaline. Potato: Thick, raised, dry, granular, profuse, gray to light cream-colored growth. Indole not produced. Slight production of hydrogen sulfide. No action on the following carbohydrates : glucose, lactose, sucrose, maltose, fructose, mannitol, galactose, arabinose, xylose, dextrin, salicin, rafiinose, trehalose, sorbi- tol, inulin, dulcitol, glycerol, rhamnose, adonitol, mannose, esculin and inositol. Nitrites not produced from nitrates. Aerobic. Slight alpha hemolysis. Non-pathogenic for guinea pigs. A special semi-solid medium, the main nutritive constituents of which were pro- teose peptone, rabbit serum, gelatin, minced rabbit kidney and carbohydrates, was used for the original isolation. An incubation period of 4 to 7 days at 26° C. was necessary for the initial isolation. Subsequent trans- fers to ordinary beef -infusion agar grew out in 24 to 48 hours. Source: Isolated from media inoculated with the mycetome and ovaries of the bed- bug, Cimex lectiilarius L. A very similar diphtheroid strain was isolated from the alimentary tract of the bagworm, Thyri- dopteryx ephemerae/ ormis Haw. Habitat: Distribution in nature unknown. 16. Corynebacterium nephridii Busing et al., 1953. (Busing, Doll and Freytag, Arch. f. Mikrobiol., 19, 1953, 77.) neph.ri'di.i. Gr. adj. nephridius of the kidney; M.L. noun nephridium a nephri- dium, a little kidney; M.L. gen. noun neph- ridii of a nephridium. Description taken from Busing and Frey- tag (Zent. f. Bakt., I Abt., Orig., 160, 1954, 582). Slender rods, 0.4 to 0.5 by 1.0 to 2.0 mi- crons, with no tendency toward filamentous forms or chains; occasionally occur in a palisade arrangement. Non-motile. Gram- positive. Growth occurs on common culture media on primary isolation. Gelatin: No liquefaction. Agar colonies: 1.5 mm in diameter, round, smooth, moist, slimy, gray. Broth: Uniformly turbid; later becoming slimy with a gray pellicle with stalactite- like growths; sediment. Coagulated blood serum: No liquefaction. Litmus milk: Distinctly alkaline in 10 days. Indole not produced. Hydrogen sulfide not produced. No acid from carbohydrate media. Acetylmethylcarbinol not produced. Nitrites not produced from nitrates. Ammonia produced in peptone media. Urea not hydrolyzed. Blood agar: No hemolj^sis. Aerobic. Optimum temperature range, 15° to 37° C. Optimum pH range, 6.2 to 7.2. Source : Isolated from the medicinal leech {Hirudo medicinalis) . 17. Corynebacterium vesiculare Busing et al., 1953. (Busing, Doll and Freytag, Arch. f. Mikrobiol., 19, 1953, 76.) ve.si.cu.la're. M.L. adj. vesicularis per- taining to a vesicle. Description taken from Busing and Frey- tag (Zent. f. Bakt., I Abt., Orig., 160, 1954, 579). Slender, pleomorphic rods 0.4 by 3.0 to 8.0 microns; filamentous forms 30 microns or more in length may also occur. Non- motile. Gram-positive. Primary isolation accomplished on "fun- gus" medium, but this species can be adapted to grow on common culture media. Gelatin: No liquefaction. Agar colonies: After 2 days, 1 to 2 mm in
