26 Contributions from the Gray Herbarium 
preciable but scarcely definable habital features, is characterized 
mainly by its involucre. The 2-5-seriate phyllaries are, except in 
a few non-typical forms, distinctly divided into an ovate or oblong 
more or less ribbed and indurated pale base and a narrower her-_ 
baceous apex, such as is well seen in V. dentata (V. helianthoides) 
(t. 2. f. 8); the five series into which the section is divided are based 
largely on secondary modifications of this type. In the series 
Maculatae (t. 2. f. 3-4), the phyllaries are oblong or rarely lan- 
ceolate, and the strongly indurated and vittate lower portion is . 
distinctly pallid and thinner on the margin, and (except in V. adeno- 
phylla) considerably longer than the herbaceous apex. V. adeno- 
phylla, although of this series, shows both in habit and involucre 
some approach to the series Dentatae. Through var. latisquama of 
V. cordifolia the otherwise distinct series Grammatoglossae is closely 
connected with the Maculatae. The typical involucre of the Gram- 
matoglossae is few-seriate, the phyllaries lanceolate, acuminate, and 
subherbaceous throughout, with almost no differentiation into 
upper and lower regions of different texture. So it is in V. cordifolia 
var. genuina (t. 2. f. 6); but in var. latisquama (t. 2. f. 7), which 
differs in no other feature and is closely connected with the type 
by a series of intermediates, the phyllaries are in no way to be 
distinguished from the type just described for the Maculatae. A 
slight approach to the same condition is also observable in V. 
Purpusii and V. grammatoglossa. 
The typical series Dentatae is distinguished by its peculiar phyl 
laries with pale, indurated, and ribbed ovate base and abruptly 
narrowed herbaceous tip, a form running with only minor varia 
tions throughout the whole series, although sometimes, as in V. 
lanata, somewhat obscured by a dense pubescence. Very similar, 
except for its narrower ‘phyllaries, is the series Pinnatilobatae. 
The three species comprising the Brevifoliae (t. 2. f. 9-10), which 
for the rest are very distinct in habit, have a 3—4-seriate grad- 
uated involucre of mostly ovate phyllaries more or less callous 
mucronulate at tip and nearly homogeneous in texture, with only 
slight traces of ribbing below and very obscure herbaceous ape%; 
but in occasional specimens of V. brevifolia the characteristié 
ovate phyllary with abruptly narrowed more herbaceous tip ® 
evident, and confirms the reference of the series to the sectio? 
Chloracra. : 



