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AMERICAN JOURNAL OF BOTANY [Vol. 10, 



the next three, one of Hispaniola and two of Cuba, have progressively nar- 

 rower and more revolute leaves and smaller and fewer heads. The group 

 culminates in a fifth species, V. corallophila Gleason of Cuba, with linear 

 leaves revolute to the midvein, n-flowered heads, and i-headed cymes 

 which appear as single axillary heads. 



A fifth species-group, the Gnaphaliifoliae, also appears to be derived 

 from V. sericea or some species similar to it. There is the usual terminal 

 head, subtended by two primary cymes, and numerous other cymes arise 

 from the upper axils. They are usually flexuous, spreading or ascending, 

 and only occasionally branched. Such structures point unmistakably to 

 an origin within the Arborescentes, with which they share many structural 

 features and from which they are indeed rather weakly separated. The 

 three species are all Cuban. In this group axillary branches do not con- 

 tinue the vegetative growth, but the whole herbaceous stem dies and is 

 replaced by new growth from the perennial base. 



All groups heretofore described in this general series have acute or 

 acuminate involucral scales. The sixth, the Acuminatae of Jamaica, have 

 obtuse scales, and also differ from the Arborescentes in their resinous-dotted, 

 non-papillose leaves and in their flattened and twisted pappus bristles. 

 Nevertheless, the simplest species of this group bears a general resemblance 

 to V. arborescens; has been placed adjacent to that species by Ekman, and 

 may have been derived from it. I fail completely to see any resemblance 

 between this group and the Fruticosae, as has been claimed by Ekman. V. 

 acuminata Less, is the common species of lower elevations. V. pluvial is 

 Gleason, the high-mountain derivative, presents an inflorescence of short, 

 much congested cymes, aggregated in subcapitate clusters. 



The seventh and last group of this series, the Fruticosae, includes one 

 species of Hispaniola and eight of Cuba, particularly of the mountains of 

 the eastern part. Many of these are poorly known, some by a single col- 

 lection, and the number of species may easily be subject to increase or de- 

 crease as further collections are accumulated for study. From the inflores- 

 cence standpoint, they exhibit the simplest scorpioid cymes to be found in the 

 West Indies. They are mostly straggling vinelike plants with indeter- 

 minate growth. At some distance above the base the main axis ends in a 

 terminal head, while immediately beneath it a lateral branch, diverging 

 at a small angle, continues the sympodial axis and bears heads in the same 

 way. The heads are separated by internodes about equal to those of the 

 sterile section of the stem in length, they are subtended by bracteal leaves 

 which in almost all species are virtually indistinguishable from the cauline 

 in size and shape, and furthermore the cyme axis is frequently prolonged 

 after flowering into a leafy, sterile stem. In their leaf habit and papillose 

 pubescence they approach V. gnaphaliijolia; in other features they have no 

 near relatives in the West Indies and apparently none in South America. 

 Nevertheless, they offer no new structural features to separate them from 



