FAMILY III. STREPTOMYCETACEAE 



817 



taining to Horton; named for the Horton 

 War Hospital, Epsom, England. 



Vegetative growth: Typical germination 

 into very slow -growing unicellular myce- 

 lium composed of long, slender, straight, 

 branching filaments. 



Aerial mycelium: Very sparse, straight 

 aerial mycelium produced only once on po- 

 tato. Non-acid-fast. 



Gelatin : Round cream-colored colonies on 

 surface and a few mm below. No liquefac- 

 tion. 



Agar: Very slow growth, a few smooth 

 cream-colored coiled colonies in 19 days; 

 after 2 months, liberal, irregular, convo- 

 luted growth. 



Glucose agar: Coiled and heaped up 

 cream-colored translucent masses; after 2 

 months, growth rounded, elevated, ridged 

 outwards from hollow center. 



Glycerol agar: Coiled, colorless, lustrous 

 patches, isolated colony with central de- 

 pression. 



Serum agar: Poor growth, small amor- 

 phous cream-colored mass. 



Inspissated serum: Intricately coiled 

 cream-colored growth. No liquefaction. 



Broth: Flakes. 



Synthetic sucrose solution: Poor growth, 

 a few flakes. 



Synthetic glycerol solution: Delicate 

 white flocculi at base. 



Litmus milk: Green surface growth, 

 liquid hydrolyzed, partly clear purple; 

 later decolorized, brown. 



Potato agar: Colorless blister colonies in 

 one week; dull green heaped and coiled 

 mass after 3 weeks; medium becomes 

 .slightly discolored. 



Potato plug: After 3 weeks, abundant, 

 colorless, umbilicated, round colonies, 

 some coiled in raised masses; later, liberal 

 olive-green growth, piled up, dense, velvety 

 gray green aerial mycelium at top of slant, 

 small round fluffy white colonies in liquid 

 at base. 



Source: Isolated from pus containing 

 typical actinomycotic granules from pa- 

 rotid abscess. 



Habitat: Found in human infections so 

 far as known. 



145. Streptomyces beddardii (Erikson, 

 1935) Waksman and Henrici, 1948. (Aciino- 

 myces beddardii Erikson, Med. Res. Council 

 Spec. Rept. Ser. 203, 1935, 36; Waksman 

 and Henrici, in Manual, 6th ed., 1948, 963.) 



bed.dar'di.i. M.L. gen. noun beddardii 

 of Beddard; presumably named for the 

 surgeon who first secured this organism. 



Vegetative growth: Rapidly growing, 

 dense, spreading mycelium composed of 

 very long, slender filaments, many wavy or 

 closely coiled, particularly on glucose agar; 

 spirals less marked or lacking on poorer 

 nutritive media like synthetic glycerol agar 

 or water agar. 



Aerial mycelium: Sparse, short, straight 

 on synthetic glycerol agar, much slower 

 and more plentiful on glucose agar; later 

 shows long, very fine spirals breaking up 

 into small ellipsoidal conidia; aerial hyphae 

 straighter and more branched with shorter 

 conidiophores on starch agar. Non-acid- 

 fast. 



Gelatin: Dull white flakes sinking to 

 bottom as medium liquefies; liquefaction 

 complete in 8 days. 



Agar: Colorless, coherent, wrinkled, 

 membranous growth with submerged mar- 

 gin; after 3 months, medium discolored, 

 scant white aerial mycelium at top. 



Glucose agar: Wrinkled membranous 

 growth; after 2 months, scant white aerial 

 mycelium. 



Glycerol agar: Small, cream-colored, dis- 

 crete colonies becoming confluent, under 

 surface much buckled. 



Potato agar: Moist, cream-colored skin, 

 convoluted, closely adherent. 



Ca-agar: Extensive, moist, cream-colored, 

 wrinkled, membranous growth. 



Coon's agar: Scant, cream-colored, mem- 

 branous growth. 



Starch agar: Spreading, colorless growth, 

 considerable white aerial mycelium. 



Blood agar: Hemolysis. Growth in uni- 

 formly striated colorless bands, occasional 

 round colonies at margin. 



Donset's egg medium: Extensive, very 

 wrinkled, membranous growth, surface 

 bright yellow. After 2 months, considerable 

 liquefaction. 



