SEGREGATES OF RHUS. 131 
Sand dunes along the southern shores of Lake Michigan, 
the type in U. S. Herb., from Clarke, Indiana, 1897, by L. M. 
Umbach. 
S. ILLINOENSIS. Evidently a larger shrub freely branching, 
the twigs pubescent: foliage scantily pubescent above, beneath 
almost villous-tomentulose, along the veins fairly hirsute: term- 
inal leaflet 24 inches long, rhombic-ovate, cuneate and entire at 
base, above this each margin evenly and very obtusely 5 to 
7-crenate, the pair 3-crenate on one side, 5-crenate on the other: 
bracts of the several spikes tomentulose-ciliate, the back 
glabrous: 
This is a shrub of central Illinois represented in U. S. Herb. 
as collected by Dr. Brendel in 1878. 
S. FORMOSA. Branches glabrous except a few scattered 
pilose hairs, but foliage villous-strigose on both faces, the veins 
beneath hirsute: terminal] leaflet 2 inches long, ovate and acute 
above a very short and abrupt cuneate base, each margin very 
evenly and beautifully 8 to 10-crenate, laterals smaller, hardly 
inequilateral, rounded at the sessile base, subserrate-crenate on 
both margins: fruits very large, hirsute. 
Sandy woods at Cobden, extreme southern Illinois, 8 June, 
1885, M. B. Waite. Shrub with beautiful foliage strongly 
characteristic. The locality is noted as that of a number of 
local species. 
S. SEROTINA. Growing twigs delicately puberulent, the 
mature glabrous: foliage in maturity vivid green and somewhat 
shining as if glabrous, under a lens seen to bear scattered short 
hairs everywhere, the veins quite pubescent on both faces; term- 
inal leaflet 2 inches long or more, 14 wide, cuneate-obovate, 
obtuse, each margin above the middle with 2 or 3 broad shallow 
crenate lobes each crenate-toothed, the pair much smaller, 
round-oval very obtuse and obtusely crenate: spikes short, 
thyrsoidly congested near the ends of the twigs; flowers appear- 
ing late, with the foliage almost full-grown: fruit hirsute. 
Species of western Missouri, remarkable among Atlantic slope 
species on account of its late time of flowering. It has been 
distributed by B. F. Bush, from Independence (in flower) and 
from Eagle Rock (in fruit). 
