404 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 6 



NOTES ON OREGON COCCINELLIDJE 



By H. E. EwiNG 



Oregon AgncuUural College, Corvallis, Oregon 



For almost two years the writer has taken field notes on the more 

 common species of Coccinellidse found in Oregon. Several experi- 

 ments also have been made with them in the laboratory in order to test 

 their fecundity, the stability of varieties, and the economic value of 

 the different forms. From these field notes and laboratory records 

 the following account has been prepared. 



Relative Economic Importance of Different Species Found 



IN Oregon 



The most abundant and the most important species of Coccinellidae 

 found in Oregon is Hippodamia convergens Guerin. It is found every- 

 where in the lower altitudes of western Oregon in the spring and sum- 

 mer, and in the higher altitudes during the fall and winter. It is 

 found in eastern Oregon, but may not have a general distribution 

 there. 



The next most abundant and most important species found here is 

 Hippodamia spuria Leconte. During the month of September, 1912, 

 I collected a hibernating mass of this species, found in company with 

 H. convergens Guerin, from the top of Mt. Chintimini (about 4000 ft.). 

 Out of 256 individuals obtained, 64 were H. spuria Leconte and 192 

 were H. convergens Guerin. This is about the average ratio of the two 

 species as found during the summer time feeding in the valley. Next 

 in abundance, but probably not in importance is Coccinella novemnotata 

 Herbst. Then comes perhaps Chilocorus bivulnerus Muls. and Cyclo- 

 neda sanguinea Linn. While these two latter species are not so abun- 

 dant as Coccinella novemnotata Herbst., their activities are directed 

 against more serious pests. Psyllobora twdata Leconte appears to be 

 the most abundant species found among the foothills and mountains 

 in the summer. It is not of special economic importance as yet as it 

 seldom is found in the valleys on cultivated plants. Smilia misella 

 Leconte is present in the Willamette Valley, and does good work 

 against the San Jose Scale. Adalia bipunctata Linn., Hippodamia 

 parenthesis Say, and Coccinella transversoguttata Fald. are present in 

 considerable numbers, but never are of prime importance. 



Migration and Hibernation Habits 



Late in July ot early in August many of our most common coccinel- 

 lids run short of aphid food, and for a while will be found in great 



