DIPHTHEROID ORGANISMS 27 



C. auris (Graham Smith) Eberson. Gram-positive, nonsporeform- 

 ing, does not liquefy gelatin. Long barred or granular, often clubbed. 

 Grows scantily on agar. Acid in dextrose and maltose, but not saccha- 

 rose. It is often virulent for guinea-pigs. Isolated from ear. 



C. cerebralis sp. nov. (Fig. 11). Gram-positive, ovoid or coccoid, 

 honmotile, nonsporeforming, does not liquefy gelatin. Grows rapidly 

 at room temperature and at 37 C. on agar. On Loeffler's serum, growth 

 is white and moist. Vigorous acid production in dextrose, lactose and 

 maltose. Avirulent for guinea-pigs and rabbits. Isolated from brain. 



GROUP 4. Nodosum. Type C. nodosum (Migula) Eberson. 

 Large, clubbed forms markedly segmented. Does not form spores, is 

 gram-positive, nonmotile, does not liquefy gelatin, white growth on 

 agar. Acid in dextrose, saccharose, maltose, and dextrin. Found fre- 

 quently in urine and the urogenital tract. Avirulent. 



C. acidum sp. nov. (Figs. 1, 2). Gram-positive, nonmotile, small 

 rods, with abundant white, glistening growth on agar. No spores, is 

 aerobic and does not liquefy gelatin. Produces large amounts of acid 

 in dextrose, lactose, saccharose, maltose, mannite and dextrin, but does 

 not attack raffinose. Isolated from urine. Avirulent. 



C. ascites sp. nov. (Fig. 8). Gram-positive, small rod with numer- 

 ous club-shaped forms on first isolation. Nonmotile, nonsporeforming, 

 does not liquefy gelatin, grows abundantly on agar and Loeffler's 

 serum. Forms acid in dextrose, saccharose, maltose, mannite and 

 dextrin. Avirulent. Isolated from ascitic fluid. 



C. flocculens sp. nov. (Fig. 13). Gram-positive, nonmotile, clubbed 

 or barred forms, does not form spores or liquefy gelatin. The organ- 

 ism grows moderately on agar and Loeffler's serum at 37 C. At room 

 temperature slight growth. Neisser's granules present. Produces acid 

 in dextrose, lactose, saccharose, maltose and dextrin. Hea-vy flaking 

 with sediment without clouding in broths. Isolated from a suppurat- 

 ing appendix. 



GROUP 5. Pigment-forming Diphtheroids. Type C. hoagii 

 (Morse) Eberson. Medium sized bacterium with solid, barred and 

 wedge-shaped forms with abundant but imperfect granules. On serum 

 a heavy, confluent, glistening growth with a characteristic, salmon-pink 

 color. Gram-positive, forms no spores, does not liquefy gelatin, non- 

 motile. Produces acid in dextrose and saccharose, but not in maltose. 



C. aurantiacum sp. nov. (Fig. 5). Gram-positive, small and coc- 

 coid, nonmotile, nonsporeforming, does not liquefy gelatin, not acid- 



