51 

 still green. OJhis, however, is lilcely to te mistaken at time-s for ,the 

 natviring of the plant. Usually the sclerotia are formed in the lower 

 half of the culm and fill its entire vertical section, tut they may 

 frequently be formed , above the middle and even near the head. The method 

 of liberation of the solerotia is very interesting. The culm is killed and 



consequently becomes dry about the time that the sclerotia are matute. 

 In drying, the sclerotia curve into a segment of a circle, thereby ruptur- 

 ing the tissues and falling to the ground. The external resemblance of 

 the sclerotia to those of Claviceps pur"purea is verjr marked, 



CXaviceuss cinereum Griffiths on Hilaria inntica 

 and H. cenchroides . Caohise, Arizona (80) 



Thfe stsl&i^ist- of this species are clavate, gradually tapering 

 up\vard, straight, curved, twisted, or contoured, 1.5 - 3 cm. in length by 

 1.75 to 2.5 mm. in diameter at the base, very viscid while developing, with 

 the base permanently invested by the flowering glumes of the host, v*iich 

 are smooth, shining, black and closely adherent, smooth as far as covered 

 by the glumes, and reticulated for EDiae distance above this. The reticu- 

 lations gradually disappear upward and merge into closely placed longi- 

 tudinal striations, ishich in turn disappear near the apex, vitoere the surface 

 is nearly anooth or irregxilarly roughened. They are dark grey at the base, 

 but gradually fade out to a very light grey or alm.ost white at the apex. 

 In sections the base possesses an external zone of a dark grey color on the 

 outside, within which is a much wider distinctly marked zone of a very 

 light grey, vshile the center, less definitely bounded, is almost pure lAhitCA 

 At the apex these divisions are absent. Stromata are erect, erumpent with 

 cylindrical or usually slightly fusiform, short, stout, alicost white stipe, 

 and a subglobose head, 1.75 to 2.75 ram. in diameter, usually slightly 

 flattened below and overlapping the upper end of the stalk. The head is 



