154 IOWA ACADEMY OP SCIENCE 
For the sake of comparison, let us consider much more briefly 
the flora of one other locality, namely, that of the neighbor- 
hood of the town of Bend, situated on Des Chutes river, about 
twenty-flve miles southeast of Sisters. 
The road between Sisters and Bend leads through a some- 
what diversifled region, parts of which are under cultivation, 
but much of it arid, stony and broken. Yellow pine and juniper 
are abundant but unevenly distributed, and sagebrush and rab- 
bit bush {Chrysothammis) are everywhere in evidence, though 
not dominating the landscape. 
Only one day (July 27) was spent at Bend, which allowed 
but a very limited survey of the flora. In general it closely re- 
sembles that of the neighborhood of Sisters, but in regard to 
moisture the conditions are more severe. The elevation is a 
little greater, and the annual precipitation about 400 mm. 
In the narrow strip, of bottom land along Des Chutes river 
there is a copious vegetation of mesophytic species, including 
among forms not found at Sisters, Monolepis nuttalliana^ Mono- 
lepis spainlata, Ribes irriguiim {?), Senecio triangularis^ and 
Senecio sp. 
In the w^ater and in mud along the margin of the stream were 
several widely distributed hydrophytes : Potamogeton perfoliatus 
ricliardsonii, Anackaris canadensis, Carex aquatilis, BatracMum 
aquatile, and. Callitriche verna. 
On land a little higher, but still affected to some extent by 
the proximity of the river, were found, in addition to many 
noted at Sisters, Tkely podium sp.. Lathy rus oregonensis, Rhus 
toxicodendron, Phacelia sp., Gapnorea nana, Gollinsia tenella, 
and Car duns undulatus. 
On the dry uplands sagebrush and rabbit bush predominate, 
with yellow pine and juniper, which have become less abundant 
as we have moved eastward. Here also we And Festuca octo- 
flora, Eriogonum vimineum, Delphinium depauperatum, Lu- 
pinus .aridus, and several others. 
This brief discussion should serve to give some idea of the 
Arid Transition flora of central Oregon, though the area cov- 
ered by the observations was too limited to yield a very ex- 
tensive list of species, and the season too advanced for the early 
vegetation. 
The following list includes practically all the species that 
were noted from the time we reached the eastern edge of the 
