FIELD OBSERVATIONS ON THE SO-CALLED ANEMONE 293 



Professor Cockerell has kindly furnished also the following list of 

 the insects which he and Mrs. Cockerell and Professor Bethel of 

 Denver found on the flowers of Pulsatilla in the spring of 1906. 



Bees 



Andrena carlini Cockerell, April 14 — male (E. Bethel) 



Halictus lerouxii Lepeletier, females, April 14 (E. Bethel); Abundant, April 20 

 (T. D. A. & W. P. Ckll.). 



Halictus cressonii Robertson, female, April 16, Gregory Canyon (T. D. A. Ckll.). 



Agapostemon texanus var. subtiHor, Cockerell, female, April 20 (W. P. Ckll.). 



Bombus nevadensis Cresson, female, are found at rest on outside of flower, April 

 20 (T. D. A. & W. P. Ckll.). 



Andrena prunorum var. gillettei, Cockerell, male and female, April 20 (T. D. A. & 

 W. P. Ckll.). 



Nomada pulsatillae Cockerell, April 20 (T. D. A. Ckll.). 



Nomada undulaticornis Cockerell, April 20 (W. P. Ckll.). 



Osmia olivacea Cockerell. Boulder, April 20 (W. P. Ckll.). 



Osmia pulsatillae Cockerell. Boulder, April 20 (W. P. Ckll.). 



Osmia aprilina Cockerell. Boulder, April 20 (T. D. A. & W. P. Ckll.). 



Sphecodes hesperellus pulsatillae Cockerell. Boulder, April 20 (W. P. Ckll.). 



Moths 

 Plusia sp., April 20, sucking (T. D. A. & W. P. Ckll.). 



Explanation of Figures 



Fig. I. — Pulsatilla hirsutissima (from Ramaley's "Wild Flowers and Trees of 

 Colorado."). 



Fig. 2. — Carpels, stamens and nectar glands of a normal flower. 



Fig. 3. — Side view of a double flower, showing petaloid segment of upper involucre. 



Fig. 4. — Side view of another double flower, showing the flower sessile upon the upper 

 involucre, one of the segments of which is formed by a sepal. 



Fig. 5. — Side view of abnormal flower, showing lobed sepals; segments of the in- 

 volucre in two rows. (This specimen was kindly furnished by Professor George L. Can- 

 non of Denver.) 



