The Ustilagineae, or Smuts, of Connecticut. 



GENERAL CHARACTERS OF THE SMUTS. 



The Ustilagineae are an order of parasitic fungi commonly 

 known as the smuts, of which corn, oat, and onion smuts are 

 familiar examples. See Figs. 55, 43, 42. Thus the more evi- 

 dent characters of these fungi are the black, dusty masses that 

 break out on the surface of the infected plants (hosts). In 

 these macroscopic characters the smuts are often very similar 

 to the rusts, but with a little experience one can readily dis- 

 tinguish them from these even with the naked eye. The dusty 

 livedo stage of the rusts, for instance, is of a lighter reddish 

 color, and the darker teleuto stage is usually more firmly em- 

 bedded in the plant tissues, than are the smuts. Not all of the 

 smuts, however, produce dark dusty outbreaks, since the white 

 smuts are light colored and usually permanently embedded in 

 the tissues of the host. Generally they occur in the leaves, 

 and often are distinguished by light colored spots produced 

 without distortion of tissues. More experience is needed to 

 distinguish these forms. See Figs. 29-34. 



The smuts occur on a great variety of flowering plants, 

 and at least 35 different families of plants in North America 

 and 17 in Connecticut are subject to their attack. The 

 grasses, however, are by far the most frequent hosts. Be- 

 tween 500 and 600 species of smuts have been described from 

 different parts of the world, and over 200 of these occur in 

 North America. The number of species known from this 

 state * is 50, and these represent 12 of the 19 genera reported 

 from North America. While time no doubt will reveal a few 

 more species and a greater number of hosts not reported here, 

 we may still consider the group rather thoroughly worked up, 

 since, as yet, only one other state has reported a greater num- 

 ber of species. 



* The list of smuts reported in this paper is based chiefly on the collections 

 made by the writer during the past three seasons. Specimens of these are to be 

 found in the herbarium of the Conn. Agr. Exp. Station at New Haven and in the 

 writer's herbarium. Collections made by others are indicated in each case by the 

 name of the collector. 



