12G 



1. A. acaulis. Cespitosc, with peduncles 4 to 10 inches 

 high, often much longer than the leaves: leaflets ovate, inegularlv 

 toothed and cut, soinetimes almost pinnatitid: umbel 8 to ir)-raved; 

 rays 5 to 10 lines long: fruit almost sessile, 1 '4 lines long. (Fig. 

 147.) — Dewcya { ?) aranlis Torrey, l*acif. R, 

 ciadhini acaulc Gray, Proc. .Vm. Acad. \\\ 

 Gray, 1. c. viii. 288. Miiscninni (Ircowi Gr:i 

 (?) Hallii Watson, 15il>l. Index. Poly pet. 

 C. k. R. Bot. Ciazettcj xii. 187, foot-note. 



In the fool-hills of Colorado and New Mexico. Fl. May. 



The history of this species has been somewhat remarkable. Not only has 

 it been referred to six genera, but it has stood under three of them at the 

 same time, lleferred first doubtfully to Jhweiia by Torrey in \s:>{;, it was 

 transferred by Gray to OreoxciiuJiuin in ISCH. It then turned up in the Hall 

 X' Harbour collection and was described as SeseJi Hnllii Gray in 1S70. A 

 year or two later it was sent to Dr. Gray by E. L. Greene, and appeared in 

 1S72 as a new species of Mii-senium, M. Groenei Gray. At this time the 

 same plant was appearing in our publications under three names, Oreoft- 

 eiadium acaide, Sencli Hallii, and Muxe.ninm Groeiiei. all of Gray. In his 

 Bibliographical Index. Watson referred it doubtfully to Carnm, as ('. (?) 

 Hallii, at the same time recogniznig the identity of Sef<eli Hallii and 

 Mvseninm Greenci, and (luoting them as synonyms. In 1K87, however, in 

 Proc. Am. Acad. xxii. 47.'), Watson records the identity of OreoHciadium 

 acatile with his Cam in (?) Hallii, ar.d so the names were at last reduced to 

 one. The fruit characters are those of Zizia, and if they are to dominate 

 over every other consideration this plant must be a Zizia, as we suggested 

 in Bot. Gazette, xii. i:i7. But no character should be used too arbitrarily, 

 and the complete disimilarity of habit between the recognized species ot 

 Zizia and this species seems something that cannot be neglected. If such 

 a thing is to be neglected in this case, consistency would demand a con- 

 solidation of genera such as we are not at present disposed to accept. 

 If this plant, then, is not a Zizia, nor any of the numerous genera pro- 

 posed for it, a genus must be made for it, for surely, if a plant 

 does not satisfy any genus, it must be sui r/eiwriH. That it does 

 not satisfy the den)ands of any recognized genus is to be inferred 

 from its strange history; but it may be proper to point out a few of the 

 reasons why it t^annot belong to any of the genera heretofore proposed for 

 it. It is hardly necessary to show why it cannot be a Velwu (Deweua). 

 From Orcu»('i(uliiiin it differs in its prominent calyx-teeth, pinnate leaves, 

 and yellow flowers; from Seneli in its laterally flattened fruit, yellow flow- 

 ers, and whole habit: from MitHnniuiii in its much more prominent ribs, 

 strengthening colls, solitary oil- tubes, almost plane seed- face, and simpler 

 leaves; from Varum in its depressed stylopodium, yellow flowers, and its 

 general habit. Taking its habit and fruit both into consideration it is more 

 nearly related to Mu/tenium than any other genus. For the reasons given, 



