74 



CULTURAL STUDIES OF SPECIES OF PENICILLIUM. 



incolorato; fructibus conidicis usque 100 longis, e basidiis sessilibus, solitariis vel verti- 

 cillatis, aut, e ramis brevissimis vel apicibus hyphorum aeriorum, 1, 2, 3 verticillos 

 ramulorum et basidiorum, catenas longas et divergentes conidiorum gerentum; basidiis 

 basidibus incrassatis, apicibus acuminatis et divergentibus, 7-10 longis; conidiis 

 2.5-3X2/* ellipticis, lsevibus, pallide lilacinis. 



Coloniis gelatinam lente liquefacientibus, alkalinis lacmo. 

 Comm., Prof. G. F. Atkinson et C. W. Edgarton, Ithaca, N. Y. 



Cultivated in pure gelatin or bean agar white, white to pale lilac in cultures con- 

 taining sugars, more or less loosely floccose with hyphse branched, septate, ascending, 3/i 

 in diameter, producing conidial masses upon very short branches irregularly distrib- 

 uted, or becoming conidiophores toward the apex; reverse of colony not discolored; 

 conidial fructifications up to 100/x in length, consisting of solitary, sessile conidiiferous 

 cells, or verticils of conidiiferous cells, or short branches bearing 1, 2, or 3 verticils of 

 branchlets and conidiiferous cells with long, tangled chains of conidia. Conidiiferous 



cells flask-shaped, divergent at 

 the apices, acuminate, 7-10/* in 

 length ; conidia elliptical, smooth, 

 2. 5-3 by 2fi, thin walled, pale 

 lilac. Colonies slowly liquefy 

 gelatin, with strongly alkaline 

 reaction. 



Received from Prof. G. F. At- 

 kinson and C. W. Edgarton, 

 Ithaca, N. Y. 



A relationship of this spe- 

 cies to the common green 

 forms is very doubtful. The 

 chains of conidia produced 

 break up so quickly and 

 completely in mounting in 

 fluid for examination that it 

 is often difficult to find even 

 a single conidium attached 

 to its sterigma. The hyphae 

 with branches and basidial 

 cells, aside from the produc- 

 tion of long conidial chains, 

 might readily be placed in any one of several hyphomycete genera. 

 The form of conidial fructification varies from a single conidiiferous 

 cell or basidium with a chain of conidia upon an aerial hypha to a 

 single verticil, or a branch with two or three successive verticils and 

 even to a terminal fructification allying it with the typical penicillate 

 forms. 



CULTURAL DATA. 



Color white to a characteristic lilac shade; reverse of colony white; color in media, 

 none. 



Odor, none. 



Fifteen per cent gelatin in water, fair growth, not heavy, white; liquefaction 

 rather slow — 14-16 days, litmus reaction strongly blue Peptone milk sugar gela- 



FiG. 30. — Penicillium lilacinum: a, b, c, short conidiophores 

 and verticils of conidiiferous cells showing the various branch- 

 ing and arrangement of cells (x 1,600); d, conidiiferous cell, 

 solitary and sessile on an aerial hypha, not uncommon in 

 this species (X 1,600); e, conidia (X 1,600); /, g, ft, sketches of 

 conidial fructifications, varying from a single chain to a typi- 

 cal penicillate form (X 260). 



