324 Howe : Preliminary notes on the genus Usnea 



distributing had been made, which is little to be wondered at, con- 



M 



with in endeavoring to help others. One specimen, no. 52 of the 

 " Decades/' is also correct. With no. 269 of the former distri- 



5 



pL 



?pap 



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over, the locality, Wellesley, Mass., is not within the range of 

 plicata^ so far as I have observed it or according to Tucker- 

 man, whereas it is a region where trichodca is common. It 

 is curious that no. 160 of the *' Boreah-Americani" distribution 

 is not only labelled trichodca^ but contains excellent fruited speci- 

 mens from Brewster, Mass. This mistake of Miss Cummings only 

 goes to prove the undue stress laid on the presence or absence 

 of apothecia and the difficulty of determining specimens from 

 Tuckerman's meager descriptions in his Synopsis. U, trichodca 

 bears apothecia frequently, true plicata never or very rarely, and 

 is without lateral fibrils. These two statements are explanatory 

 of Miss Cummings' error. The including of longissima from 



la^yp 



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point to the fact that she believed both species to occur in the re- 

 gion of Wellesley. Feeling as I do, that Miss Cummings, or per- 



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haps one of her aids, in this instance was mistaken, I am sure I 

 have no right, at least, to let the matter go without mention, as I 

 have said before *'that one specimen wrongly determined may be 

 the highway for many more,*' and this is especially true of speci- 

 mens distributed in well-known exsiccati. 



It is my hope to pubhsh within a year or two a manual of 

 North American Usneas, but before this can be done I have yet 

 to examine a great many more specimens from outlying localities 

 not represented in the herbaria I have so far seen, as well as to go 

 over the literature with renewed care. The appended records are 

 taken from all the published New England lists of which I have 

 knowledge, and serve to show how sadly this side of the work has 

 been neglected, and how much is left to be accomplished in the 

 study of distribution. I have examined many of the specimens 

 on which the annotations in these lists were made, as many erro- 



