386 PROCEEDINGS OF THE AMERICAN ACADEMY 



214. Peucedandji leiocarpum Nutt. 1. c. Seseli leiocarpum 

 Hook. 1. c. t. 93. 



215. Sium lineare Michx. ; Gray Man. ed. 5, p. 196. 



216. Osmorrhiza nuda Toit. Bot. Whippl. This does not seem 

 to pass into 0. brevistylis, with which it has been perhaps unavoidably 

 confounded. 



217. Glycosma ambiguum, n. sp. Distinguished from G. Bolan- 

 deri by greater smoothness, more acute and incised leaflets, longer 

 pedicels, and especially by the shorter fruit (6 or at most 7 lines long), 

 which is decidedly contracted at the commissure, and the ribs towards 

 the base more or less setose, — characters which, with the habit, ally 

 this plant to Osmorrhiza much more than to Myrrhis. While Bentham 

 and Hooker referred Nuttall's Glycosma to Myrrhis, they neglected 

 to extend the character so as to include it. It is now clear to me that 

 the genus should be kept distinct both from Myrrhis and Osmorrhiza, 

 although between the two. The cardinal characteristic of Osmorrhiza 

 is the caudate attenuation of the base of the carpels. Glycosma has 

 none of this, but the base is abrupt and obtuse. From Myrrhis it dif- 

 fers in habit, geographical distribution, absence of involucels, and strik- 

 ingly in the merely costate (not enlarged and wing-like) juga. As to 

 the breadth of the commissure or contraction of the sides of the fruit, 

 while the original species is much like Myrrhis in this respect, the pre- 

 sent one is more like Osmorrhiza.* 



* Glycosma Nutt. in Torr. & Gray, Fl. 1, p. 639. Myrrhis Sp Glycosma Gray, 

 Proceed. Acad. 7, p. 346. 



* Fructus laevis, basi obtusissimus, commissura lata. 



G. occidentale, Nutt. 1. c. Pruinoso-puberula ; foliolis oblongo-lanceolatis 

 oblongisve serratis rare- incisis ; urnbellas fructiferae radiis suberectis, pedicellis flores 

 sterilia pi. m. superantibus ; fructus jugis acutis. Myrrhis occidentalis Gray Proc. 

 Acad. 1. c. 



G. Bolanderi, subpubescens ; foliolis ovatis magis incisis ; umbella; fructiferae 

 radiis patentibus, pedicellis floribus sterilibus brevioribus ; fructus jugis obtusis. 

 Myrrhis Bolanderi, Gray, 1. c. 



* * Fructus breviusculus, basi acutiusculus ad comraissuram parum constrictus, 

 costis inferne pi. m. setulosis (nunc denudatis). 



G. ambiguum, n. sp. Elatum, glabrum ; petiolis costisque subtus pilosiusculis ; 

 foliolis ovato-oblongis acutis dentato-incisis sajpiusque 2 - 3-fidis tenuiter membrana- 

 ceis; umbellae fructiferae radiis patentibus; pedicellis flores sterilia aequantibus ; 

 fructu(6-7 lin. longi) lineari-oblongo utrinque acutiusculo. — Foot of Cascade 

 Mountains, Oregon. 



I may here append the characters of a new species of Musenium, viz. : — 



