446 RYDBERG: PHYTOGEOGRAPHICAL NOTES. 
4. HoG-BACcKs* 
Common to the Southern and Northern Rockies 
ee Hepburnit 
Engelmannu 
occidentalis 
“ phaenocephala 
obtusata 
rupestris 
“ Hellert 
Ross 
Eriogonum arcuatum 
flavum 
umbellatum 
Oreobroma pygmaea 
Silene acaulis 
Cerastitum Behringianum 
Alsinopsis Nuttall 
is obtustloba 
Anemone parviflora 
os tetonensis (Utah) 
Drummondii 
Pulsaiilla ludoviciana 
Smelowskia americana 
& lineartloba 
Draba ventrosa 
oligosperma 
andina 
crassa 
‘*  luteola 
aurea 
és 
Rhodtola integrifolia 
Ivesta Gordontt 
a divisa 
nivea 
uniflora 
saximontana 
arachnoidea 
Sibbaldia procumbens 
Dasiphora fruticosa var. 
Trifolium nanum 
Androsace carinata 
Gilia globularis 
Phlox depressa 
“ caespitosa 
Eritrichium elongatum 
argenieum 
Castilleja occidentalis 
Erigeron compositus 
‘‘  melanocephalus 
simplex 
Antennaria aprica 
“media 
: sedoides 
i umbrinella 
Chaenactis alpina 
Senecio Purshianus 
“é 
_ Artemisia scopulorum 
ee spithamaea 
Restricted to the Southern Rockies 
Eriogonum chloranthum 
" neglectum 
Paronychia pulvinata 
Arenaria Fendleri 
Thlaspi coloradense _ 
“purpurascens 
* For discussion see Bull. Torrey Club 42: 633. I915. 
