A LIST OF THE ENTOMOSTRACA OF COLORADO 
By GIDEON S. Dopps 
The Entomostracan fauna of Colorado has been but little studied and 
the records up to the present are not numerous. A brief statement of 
the work that has been done may be of interest. The writer has 
attempted to summarize all the work which has been done in the state 
and the following list probably includes all the published records. 
Prior to 1902, but ro species of Entomostraca were known for 
Colorado. Most of these were listed by naturalists with the ‘Hayden 
Survey” during the “seventies.” In 1902 Professor Beardsley, of Greeley, 
Colo., published a list of 34 species known to occur in the state. Of 
these, 24 species new to the state were from his own collections. In 
1904 Birge added 6 species and Marsh added 3 from the collections 
made by Ward in the Pike’s Peak region. A. S. Pearse in 1905 listed 
one additional species and Beardsley added one. In 1907 Juday from 
Twin Lakes added 10 to the list and in the same year Marsh gave records 
of 5 additional species. In 1905 Shantz published some valuable data 
concerning lakes in the Pike’s Peak region but gives no records of the 
species of Entomostraca collected. The above records include three 
species new to science: Diaptomus nudus Marsh and Macrothrix mon- 
tana Birge from the Pike’s Peak region and Diapitomus judayi Marsh 
from Twin Lakes. The writer during the summer of 1907 collected 5 
species not hitherto listed from the state. This makes a total of 65 
species recorded for the state. 
This list is not a long one but very little work has been done. More 
extensive collections will, in all probability, show the total number in 
the state to be considerable. ‘The wide range of climatic conditions 
may be expected to support a corresponding variety of forms. In our 
foothill and mountain region there are a large number of small lakes at 
altitudes varying from 6,000 to 12,000 feet. Little is known about the 
Entomostraca of such lakes in America and systematic study here 
should be fruitful. 
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