72 CULTUEAL STUDIES OF SPECIES OF PENICILLIUM. 



CULTURAL DATA. 



Color gray, gray -green, often gray or gray-brown when old; reverse white; color in 

 media, none. 



Odor, distinct in cane-sugar media. 



Fifteen per cent gelatin in water, medium growth, gray -green to brown when old; 

 liquefaction, none; litmus reaction neutral. Potato agar and bean agar, rather small 

 colonies, weak growth, grayish green to yellow-brown. Potato plugs, white to yellow- 

 ish brown colonies, very weak growth. Raulin's fluid, rich growth, bright green, dis- 

 tinct odor. Cohn's solution, germination only. 



Synthetic fluid (Dox's), carbon supplied as: Cane sugar, rich growth up to 30 per 

 cent. Lactose 3 per cent, slight growth. Lactic acid 0.9 per cent, medium colony, 

 light green. Levulose 3 per cent, small greenish colonies. Galactose 3 per cent, 

 growth, faintly alkaline reaction. Glycerin 3 per cent, germination only. Potato 

 starch 3 per cent, very slight growth. Butterfat, weak colonies. 



Milk, not adapted to this species, colonies grow very slowly; curdling (0.25 per cent 

 calcium chlorid added) slow — about 4 weeks; digestion, little or none; color in milk, 

 none. 



At 37° C. some growth; check at 20° C. better than 37° C. 



PENICILLIUM DIVARICATUM n. sp. 



Latin diagnosis. — Coloniis in gelatina vel agaro phaseoli cultis, avellaneis, nun- 

 quam viridibus, in substrato late crescentibus; parte aria ex hyphis fertilibus intri- 

 catis, demum fere pulverulenta; re verso incolorato; hyphis fertilibus septatis, ple- 

 rumque brevibus, repentibus vel adscendentibus; fructibus conidicis aut terminalibus 

 aut lateralibus ex hyphis fertilibus repentibus ex verticillis sessiles ramorum et basid- 

 iorum, irregulariter in hyphis fertilibus orientibus; basidiis 15-20X3//, sterigmatibus 

 longis acuminatis, in baside confertis, apice late divergentibus, catenas longas coni- 

 diorum gerentibus; conidiis ellipticis vel fusiformibus, 5-7X2.5-3^, avellaneis, 10/z 

 incrassatis 2-3 tubis germinantibus; coloniis gelatinam non liquefacientibus, alka- 

 linis lacmo. 



Legit, C. Thom, Storrs, Conn. 



Cultivated in gelatin or bean agar, yellowish brown (avellaneous), never green, 

 broadly spreading in the substratum; superficial growth consisting only of closely 

 woven fertile hyphae, becoming powdery in appearance when mature; reverse of colony 

 not discolored; fertile hyphge septate, usually short, mostly creeping; conidial fructi- 

 fications either terminal or on short branches of creeping or partially erect hyphse, con- 

 sisting of separate conidiiferous cells, of verticils, or of series of verticils of branchlets 

 and conidiiferous cells irregularly distributed along the fertile hyphae; conidiiferous 

 cells 15-20 by 3/x, with long acuminate sterigmata, broadly divergent at the apices 

 and bearing long chains of conidia; conidia elliptical or fusiform, 5-7 by 2.5-3/*, yel- 

 lowish to brownish, swelling in germination to 10/i and producing 2 or more tubes; 

 does not liquefy gelatin; litmus reaction alkaline. 



Unmistakable when once seen in culture. Found in a mucilage bottle, Storrs, 

 Conn., 1904. Later contributed by Prof. G. F. Atkinson from North Carolina. 



In common with several other forms included in the genus Peni- 

 cillium, the conidial fructifications of this species are not strictly peni 

 cillate and terminal. Every gradation is found from fruiting systems 

 typical of the genus to simple chains of conidia borne by single cells or 

 basidia upon prostrate or even submerged hyphse. It partakes, how- 

 ever, of the cultural character of the species of the genus, as shown by 

 its copious growth upon many different substrata. 



