ROSACEAE. 119 
CowANIA. 
(Family Rosaceae). 
Shrubs: evergreen. Twigs ter- 
ete, slender, from brown becom- 
ing gray with scurfy outer cortex: 
pith minute, round. Buds soli- 
tary, sessile, at first ovoid with 2 
outer scales but rather quickly de- 
veloping short branches sheathed 
by, overlapping leaf-bases. Leaf- 
scars alternate, half-round, min- 
ute, much raised on thin winged 
bases topped by the rather per- 
sistent stipules: bundle-trace 1, 
indistinct. Leaves as in Fallugia 
but very glandular-warty, or in 
one species (C. ericaefolia) min- 
ute, entire, and pungent. 
Cowania, Fallugia, and Purshia 
are three genera with rather simi- 
lar leaves. As in Potentilla, these 
disarticulate .from the top of a 
dilated persistent base correspond- 
ing to the lower part of, the petiole with stipules attached 
to its sides. Leaf-bases of this sort, which are found in a 
number of Rosaceae, are more frequent in the related family 
Leguminosae, and transitions may be found between extreme 
cases like these and the less produced but otherwise com- 
parable leaf-cushion found in the greater number of rosaceous 
and leguminous genera. 
Twigs from bristly and puberulent glabrescent. 
C. Stansburiana. 
