BOTANICAL GAZETTE. 335 



nigra, Turriiissp. Rhaphanus sativus, Sisymbrium officinale, and Nasturtium Armorackt. 



Everywhere common. Europe. 



The common white rust on cruciferous plants, distorting the leaves, stems, 

 and even the floral organs. I have found oospores in the stems and pedicels of 

 Sinapis and Raphanus. Although extremely common on Capsella and Lepidium, 

 I have not seen oospores in those plants in this country. 



33. C. cubicus .(Strauss) Lev. 



Uredo evibica Strauss Ann. Wetterauer Qesell. II. 86. 



C. cubicus Lev. 1. c; De Bary 1. c. 128 PI. II. f. 17-21 ; Bull. Buss. Inst. I. 129 ; 25th 



Rept. N. Y. Bot. 'M ; 29th Rept. 76; 30th Kept. 77. 

 C. spinulosus De Bary 1. c. 129; 29th Rept. X. V. Hot. 51. 

 Exs. Ellis, N. A. F., no. 206. 



Conidia of two kinds, the terminal ones larger than the 

 others, depressed-globose, the others short cylindrical (squarish 

 in optical section), with a thickened transverse ring. Oospores 

 brown or black, globose, exospore covered with a fine, scarcely- 

 raised, net work. 



On Tragopogon porrifolius, Ambrosia arteraisiafolia, Parthenium integrifolium, 

 Cirsium arvense. 



Massachusetts to Iowa. Europe. 



I have found oospores on all the hosts just named, and they all, as well as 

 those in European specimens, of which I have examined a large set, have an 

 exospore which at first sight appears to he granular, but which, on close exam- 

 ination, proves to be covered with a slightly raised net-work, with very small 

 meshes. In this respect European and American specimens of C. spinulosus 

 agree perfectly with C. cubicus, and the two forms should be united. Probably 

 the species appears on several other composites in this country. It is, however, 

 by no means certain that the Cystopus on Gonvolvulac.ea>, viz.: Iporrum edulis in 

 Myc. Univ. 815, Convolvulus in Ravenel Fung. Am. 501, and apparently not rare 

 from New Jersey (Halsted) on Ipomri to North Carolina, on Ipom. 

 pandurata, Ipom. trichocarpa and Ohio belongs to the present species. 

 The conidia are subcylindrical, and resemble those of C. cubicus, but I have 

 never been able to find oospores in the numerous specimens which I have exam- 

 ined, and without them one can not determine the species with any degree of 

 certainty. The Oystopus on Qonvolvulaceat is apparently the JEzidium fpomcea 

 panduranoz Schweinitz's Syn. Fung. Car. No. 454, and it is to be hoped that 

 some person will find the oospores, which should be sought in the stems and 

 petioles rather than the leaves. In this connection I would call attention to 

 the fact that a Cystopus was found on cotton leaves, in Alabama, by Prof. C. V. 

 Riley, in 1879. The discovery is of great practical importance, although, as 

 there were no oospores, the species could not be determined. 



34. C. Blitz (Bivon.) Lev. 



Uredo Bliti Bivona-Bernard in Stirp. Sic. III. 11. 



Cseoma I Uredo) 4marantfwSch.Syn.Fung. Am. Bor. no. 2853; Grevillea III. 58: 28th 



Rept. N. Y . Bot. 61. 

 Cyst. Bliti Lev. 1. c. ; De B.iry 1. c. 127, PI. XIII. f. 13-15; Bull. Buss. Inst. 429 in 



part. 

 Exs. Mye. Univ. 619 ; Ellis N. A. F. 206. 



Conidia of two kinds, the terminal subglobose, generally smaller 



