OF ARTS AND SCIENCES: MAY 13, 1873. 633 



Amphiaclnjris dracunculoides Torr. & Gray, and A. Fremontii (Am- 

 phipappus Fremontii Torr. & Gray) constitute the species. 



Pf.ntach.eta Nutt. — P. gracilis Benth. in Ic. PI. t. 1101, judg- 

 ing from the figure and description, cannot be of this genus. The 

 style-branches, even if " not quite so obtuse as represented in the 

 plate," altogether want the long linear-filiform appendage surmounting 

 the short and flat stigmatiferous portion, and, with the opposite leaves 

 toward the base of the stem (and, I may add, the beard represented 

 on the lobes of the disk-corolla), as Mr. Bentham remarks, connect it 

 technically, and it seems to me really, with Helenioidece. It appears 

 to be a species of Oxypappus. 



As to Pentachceta itself, I find no bilabiation or obliquity in the disk- 

 corollas, such as Nuttall mentions. And there are two species, which 

 may be well distinguished, namely : — 



Pentach.eta aurea Nutt., from San Diego and the vicinity, has the 

 heads perhaps always many-flowered (but the size of the head, and 

 number of the flowers varying greatly), and the scales of the involucre 

 are acute or acuminate and well imbricated, the exterior successively 

 shorter ; the rays are golden yellow, and it is not known that the 

 pappus is ever abortive. 



Pentachceta exilis (not a happy name for the larger forms) has 

 the scales of the involucre less scarious, oblong or oval, obtuse, but 

 often mucronate-tipped, all nearly equal in length; -the rays very 

 light yellow ; pappus as in the original species, or in some specimens 

 (mixed with the others) some or all of the bristles short or obsolete. 

 This equally occurs in those with rather large and many-flowered 

 and those with few-flowered heads. Either form may be rayless 

 and homogamous. But some specimens have barely 3 to 5 pistillate 

 flowers, which are destitute of ligule, the tube of the corolla only re- 

 maining. These are Apkantochceta exilis, Gray in Bot. Whippl. (Pacif. 

 R. R. Expl. 4), t. 11, which must be viewed as an occasional and 

 reduced state of a full-rayed species. It is only in the small and 

 mostly rayless forms that the corollas seem to turn purplish. 



Xanthisjia DC. It appears on the whole most proper to reinstate 

 this genus, although a transition to Aplopappus is afforded by the sec- 

 tion Prionopsis, which seemingly is best restricted, as proposed, to A. 

 ciliatus. — The following is still more worthy of generic separation, 

 and should be ranked rather with genera having paleaceous than with 

 those of setose pappus. 



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