209 



D. Boottii has been described as a variety of D. spimdosa and as 

 a variety of D. cristata, and it has been considered by many a 

 hybrid between these two. The scales of D. Boottii are more 

 abundant and of a darker brown than in either of the other two, 

 and it is glandular, a characteristic which is absent in the other 

 two. These objections may be met by considering as one of the 

 parents D. spimdosa intermedia instead of D. spinulosa. Another 

 respect in which D. Boottii differs from the other two is the posi- 

 tion of its sori nearer the midvein than in either of the others. 

 In this it is not intermediate between its supposed parents. 

 Experiments may prove D. Boottii to be a hybrid, if this fern can 

 be produced by crossing its possible parents, but until that is 

 done we are not justified in concluding that it is a hybrid. It is 

 to be hoped th^t the question may appeal to some one in a posi- 

 tion to perform such experiments. I trust also that others who 

 have had the opportunity of observing D. Boottii in the field will 

 publish such observations. 



Port Richmond, N. Y. 

 September 8, 1906. 



SHORTER NOTES 



Note ON the Identity of Trillium obovatum Pursh. — I 

 have observed in the July BuUetin of the Torrey Botanical Club that 

 Dr. H. A. Gleason, in his treatment of the pedunculate species 

 of Trilliuvi, has made an error which I think should not go un- 

 corrected. He has made T. obovatum Pursh a synonym of T. 

 erectiim L., and makes the statement that " it had white, obovate 

 petals." There is nothing in Pursh's Latin description of his T. 

 obovatnm, page 245 of the Flora Americae Septentrionalis, to in- 

 dicate the color of the petals ; but on page 246, in his English 

 notes, he distinctly states that the flowers are " dark rose-colored," 

 suggesting that they might be white when first opening. 



There is in the vicinity of Detroit a trillium that agrees ex- 

 actly with Pursh's description of T. obovatmn and undoubtedly is 

 that species which, however, should be referred to T. grandi- 

 flornni Salisb. and not to T. erectiun L. The flowers, on the 



