19 
pitate species with larger flowers come next. A. Coltoni with pur- 
ple flowers belongs to the Navajo Basin slopes. A. stenophyllus and 
Antiselli with white flowers come next, belonging to the mountain 
slopes of the northern Great Basin, the Columbia Basin, and the 
southern California plains in warmer regions, and almost connecting 
with the Inflati through A. oxyphysus. Another offshoot of the north- 
ern Sierras is in A. Californicus and inversus. 
The second branch of the Homalobi has the ventral suture less 
arched than the dorsal for the most part, and as a whole belongs in 
warmer regions or at the south. A. campestris with pods wider above 
is cosmopolitan in the mountains, even reaching alpine places. A. 
Pasqualensis ís placed here for lack of a better place, but its posi- 
tion is not determined, It is from the far south in Mexico. The 
species with pods not wider above are A. junceus and Episcopus. 
Species much as in A. campestris but with acerose leaflets are A. 
simplicifolius and detritalis. A marked differentiation of the group 
now comes in the species A. montanus which connects campes- 
tris with the humistratus group, and represents the alteration of 
campestris to thrive on the dry plains and stony forests of Wyoming 
to Arizona. A. humistratus and sesquiflorus represent a modification 
of montanus for the forests of Arizona and New Mexico to Mexico. 
Other modifications are A. sericoleucus for the Plains of Wyoming 
and Colorado, A. Gilensis for those of the Gila. A. tegetarioides for 
those of Oregon. A. quinqueflorus and Pueblae are Mexican out- 
liers. 
2. Triphylli. This group of two species represents a special 
adaptation to the wind-swept Plains. 
3. Debiles. This offshoot of the Homalobi starts off near A. 
tenellus and its lowest species doubtless is A. debilis connecting the 
group with A. tenellus of the Homalobi, and also not greatly re- 
moved from A. pauciflorus of the Inflati. Then comes A. 
Yukonensis, and leptaleus, with A. polaris last. This little known 
species is very likely to belong with A. alpinus. The Debiles all 
belong in the north in cold regions in moist places with sweet or 
acid soil. 
4. Sparsiflori. This group connects almost direct with the De- 
biles by A. leptaleus through A. sparsiflorus, with A. obcordatus next 
and A. villosus last, and belongs on the plains and prairies from Colo- 
rado southeastward. 
5. Alpini. This group is perhaps as well placed as an offshoot 
ef the Sparsiflori and closely related to the Inflati, though it is re 
lated to the Atrati and Strigulosi which represent it in the south. 
Its lowest species is doubtless A. elegans though the little known A. 
Cormani may be first, then comes the large stipuled forms A. alpinus 
end Americanus, and the small-stipuled forms aboriginum and Cot- 
toni, all with a slightly produced dorsal suture, then we come to the 
snleate and variably 2-celled forms A. Labradoricus and andinus. All 
this group belong in the high region or the far north, mostly in 
cold meadows and copses. 
6. inflati. This is an early offshoot of tbe Debiles or coordi- 
nate with it as an offshoot of the Homalobi, for A. pauciflorus is 
certainly closely related to A. tenellus. This is a group of the hot and 
variably alkaline deserts for the most part. Its two primitive species 
A. pauciflorus and miser belonging in sweet soil in the pine forests 
of the north. Among its single-celled small podded forms A. Pulsi- 
ferae and diurnus belong in the sagebrush benches of the southern 
Columbia Basin drainage and vicinity, A. pubentissimus in the Navajo 
Basin deserts in sandy places. A. sabulonum in similar places along 
the Colorado in Utah and Nevada, A. aridus in the hot deserts of the 
Death Valley-Mojave region, A. Geyeri on the sandy deserts of the 
Great Basin, A. Julianus, proriferus and metanus in the deserts of 
Lower California, A. Vaseyi, Thurberi and Palmeri in the deserts of 
