GRASSES OF IOWA. 235 



ment of Agriculture, Washington. These specimens, it appears, 

 ■came from New Jersey. It was also reported from New York 

 to Trelease by Sturtevant. Webber* reported it on Millo maize 

 in Nebraska in 1889. It was reported as common in Kansas by 

 Kellerman. f Hitchcock has kindly furnished me with speci- 

 mens from Kansas, and in Clinton's paper on Broom Corn 

 Smut the statement is made that it occurs on Early Amber, 

 Rangoon, Red Liberian and many others; also on broom corn 

 and Kafir corn. In 1899 it was found on Kafir corn at Ames 

 by Mr. Evers In Illinois it was first collected by Waited in 

 1887, at Urbana. Further localities are reported by Clinton. § 



Characters of the fungus. — The diseased plants attain their 

 normal height. The panicle is elongated and all of the seeds 

 are destroyed. In the case of broom corn as described by 

 Clinton it is as follows: "An examioation cf the brush of an 

 infected plant, unfortunately, shows that it is of a very inferior 

 grade, usually almost worthltss. Here, then, is a much more 

 important loss, for the brush is the part for which broom corn 

 is raisei. G:oi broom corn has the rays of about uniform 

 thickness and length, and all springing from a series of very 

 contracted nodes so as to give them about the same point of 

 origin. In the case of infected plants these internodes are 

 usually elongated, and the rays are of unequal lengths, so that 

 there are a series of irregular rays arranged on an elongated 

 and thickened central axis — qualities very undesirable." 



The covering of the grains is pale. At maturity the grains 

 are grayish in color. Finally the membrane becomes broken, 

 permitting the spores tD escape. The whole interior of the 

 ovary is converted into a mass cf spores, the anthers being also 

 affected. The spores are spherical, or somewhat angular, 

 rarely elliptical, 5-9.5 x 4-5.5". The spores g rtninate readily 

 when placed in water. Clinton states that spores 1 year old 

 germinate. Some writers state that spores 6.5 years old ger- 

 minate. 



Infection takes place by the penetration of sporidia as well 

 as the "infectioa threads. "' According to Clinton, entrance to 

 the plant takes place at the growing i^oint. "Thus the ger- 

 minating S2ed in its early stages is the only place where the 

 broom-corn is liable to become successfully infected. As a 



*Ann. Rep. Neb. State Board of Agrl. 1889. 214. 1890. 

 tBull. Kans. Agrl. Exp. Sta. 23. 

 *Bull. Univ. 111. Agrl Exp. Sta. 47: 376. 

 §1. c. 



