PAPERS GIVING RUSTS OF NORTH AMERICA. 179 



specimen was preserved in a paper packet, made by folding over the 

 sides of a sheet of paper until they touched or somewhat over- 

 lapped, then folding over the ends in the same manner and in the 

 same direction. On the hack of the packet an autographic record 

 was made in ink. Wlu-n a change was necessitated in the label by 

 the adoption of Link's nomenclature, or for other reasons, in many 

 cases the packet was not discarded, but refolded inside out and the 

 data replaced in the new form on the back. This conservative prac- 

 tice, doubtless adopted merely as a convenience in handling, has 

 given a chronological record that has often proved of much value 

 when studying the original material, as showing changes in Schwei- 

 nitz's views regarding the best form of the name or the identity of 

 the material. The packets were of no uniformity in size, but varied 

 from about three by six centimeters or smaller up to six by ten cen- 

 timeters, and a few still larger. 



Some thirty or forty of these packets were placed loosely in 

 large envelopes, folded in a similar manner to 22 by 38 centimeters 

 from heavy steel-blue paper, and a list of the species inclosed writ- 

 ten on the back. Three to five of these envelopes according to bulk 

 were put into a pasteboard portfolio of the same size and seven or 

 eight centimeters in thickness, and tied with tape, the back being 

 lettered with the consecutive number and the genus represented. 

 The whole collection was contained in 39 portfolios, making a series 

 of shelf volumes in outward appearance resembling a set of the 

 modern bound fungi exsiccati. All the fungi w^ere placed in one 

 series, the European, North American and Surinam specimens 

 being intermixed. 



The part of Schweinitz's work on North American Fungi with 

 which this paper has to deal is with the exception of eight species 

 comprised under the two genera Cceoma and Piiccinia. The mate- 

 rial under Cceoma, both American and European, occupies the five 

 envelopes in portfolio no. 38, and embraces 243 packets, of which 

 considerably more than half are now empty. The material under 

 Piiccinia occupies two of the envelopes in portfolio no. 39, and 

 embraces 84 packets, more than half being empty. Altogether 

 under Cceoma and Piiccinia 178 collections are European, 130 being 

 without specimens, 18 are from Surinam, 3 without specimens, and 



