
8 Contributions from the Gray Herbarium 
excepto 3-nerviae. Flor. fem. 24; hermaph. 10. Corollae non ~ 
visae. Achenia obovata marginata viridescenti-nigrescentia 15 4 
mm. longa 0.9-I mm. lata. Ovaria sterilia linearia ad apicem 
villosa pilis perpaucis praedita ad 1.8 mm. longa. — Peru: near 
Tarapoto, 1855-56, Spruce 4522 (rypr couu.: Brit. Mus., Kew, 3 
Gray Herb.). — Very distinct from any published species. 
ll. A REVISION OF THE GENUS DIMEROSTEMMA + : 
CASS 
By 8S. F. BLaKke. 
In 1848 Gardner published from Brazil a new genus of the helian- 4 
thoid Compositae which he named Serpaea in honor of Dr. Serp& 
then professor of botany in the College of Olinda near Pernambuco. — 
One of the two species on which the genus was based is a true As bo 
pilia and was referred to that genus by Baker in 1884, hav 
wrongly been remanded to Viguiera by Bentham & Hooker — 
1873. The other, S. ovata Gardn., has since 1873 been retained 12 — | 
Oyedaea, to which it was first referred by Bentham & Hooker. a 
With three new species it was taken by Baker in 1884 to constitute a 
his subgenus Serpaea of Oyedaea. . 
Recent critical study of the genera Viguiera and Oyedaea bas 
convinced me that Gardner’s genus Serpaea is well worthy af a 
generic rank. While all the some 20 species of Oyedaea have @ 
thickened laterally rounded achene bearing a pappus of two awns 
with an intermediate corona of basally fused squamellae, the igs 
species referable to Serpaea have a more or less quadrangt 
achene with a pappus of two awns only without intermediate 
corona, although in some cases the intermediateanglesof the achené = 
are prolonged into short teeth or occasionally into awDs nearly : 
or quite as long as thoseof the main angles. Thesespecies are like 
wise distinguished by the possession of a secondary involucre 
2-several herbaceous bracts outside the true more or lessindurate 
phyllaries, these accessory bracts being similar to the stem leaves 
but very much reduced in size. ‘ 
: Cassini’s genus Dimerostemma, described in 1817 from material 
in the herbaria of Jussieu and Desfontaines brought from the gat 
den of Lisbon and originating from Brazil, has ever since remained 4 
an unverified genus to synantherologists. It was placed by Bena 
Sve te 

ea 













a 
pa ae 

