VOL. Iv.] Contributions to Western Botany. 45 
Prunus demissa Walpers. An examination of all my material 
shows that the leaves are never less than subcoriaceous and often 
coriaceous. The flowers are one and one-half to two times larger 
than those of P. Virginiana. The pedicels and peduncles are 
stouter, but longer. The shape of the leaves varies, but, on the 
whole, they are narrower, the bloom on the under side of the 
leaves varies from about the same as that of P. Virginiana to almost 
white in a specimen gathered at Albuquerque, New Mexico. 
The bark is duller, but otherwise I see little difference. The 
fruit of both is very astringent. . demissa is a little stiffer than 
P. Virginiana inhabit. I am very familiar with ?. Virginiana as it 
exists in Iowa, and have abundance of material from there. I 
am very familiar with 7. demissa as it exists in Utah, Nevada, 
Colorado, and New Mexico. Allof my specimens from Colorado 
are P. demissa, JI distributed them in 1878 as P. Virginiana, as 
at that time all those forms were supposed to be P. Virginiana. I 
doubt that ?. Virginiana exists in Colorado. My studies confirm 
those of Mr. Greene, except in a few unimportant particulars, as 
given in Pittonia under the head of Cerasus. 
CYMOPTERUS, SECTION COLOPTERA (C. & R.) 
A recent examination of all my material makes it clear that this 
genus of C. & R. is not well founded. The character given by 
them in their Revision of the Umbelliferze, p. 49, is substantially 
as follows. I omit such characters as are not supposed to be 
peculiar to the genus. 
'  Coloptera. Involucre none; lateral wings of fruit corky thick- 
ened, dorsal filiform. All other characters given belong equally 
to Cymopterus. The whole genus is really founded on the corky- 
thickened lateral wings, a character that is also found in other 
Species of Cymopterus in varying degree, but is concealed by the 
prolongation of the wings beyond the thickened part. This is 
seen in C. montanus, and were it not for the greatly produced 
edge of the wing it might be taken for a Coloptera, though there 
is no thin space between the base of the wing and the seed, as is 
the case in true Coloptera. In Cymopterus Jonesii the thickening 
of the wing is carried to the utmost limit at the base, and is also 
contracted a little there at the junction with the seed. In Cymop- 
