34 BULLETIN 417, U. S. DEPARTMENT OF AGRICULTURE. 



ment was started to ascertain if predacious Calosoma could be in- 

 duced to prey upon the pest. 



In June, 1910, five males and three females of this species were 

 placed in one greenhouse, in a wire cage, 2 by 1J by 1| feet. A number 

 of asparagus plants were growing in this cage and cutworms were 

 added from time to time. 



On August 17, 1910, three adults were climbing about on the sides 

 of the cage. No dead beetles had been removed, nor had there been 

 any reproduction observed by the foreman. The cage was not 

 visited again by the junior writer until March 21, 1911, when two 

 males were active, climbing on the sides of the cage. The foreman 

 stated that the beetles were first active in the cage about February 1, 

 1911. A dead beetle was removed at that time. 



June 16, 1911, the earth in the cage containing the beetles was ex- 

 amined and three males were found in separate well-made cavities 

 at the bottom. The walls of one of the cavities was secured unbroken 

 and the beetles appeared dormant when first disturbed. On this date 

 these beetles had lived in greenhouse temperatures and conditions for 

 one year, thoroughly demonstrating their ability to withstand similar 

 conditions. The foregoing notes show that they do change their 

 habits somewhat to suit conditions, in being alternately active and 

 dormant throughout the year. Two males and two females were re- 

 placed in the cage on this date and further observations were made 

 for reproduction of the species in 1911. By August 7, one pair had 

 died and still there was no evidence of reproduction although this 

 might have taken place and the young larvae escaped through the 

 meshes of the fly screen unnoticed, but it is rather improbable. 



On the same date (June 16, 1911) seven males and six females were 

 liberated in the beds of Asparagus plumosus in an adjoining house. 

 Some of these beetles were placed upon the asparagus leaves and on 

 these they climbed for a while but soon fell to the ground and disap- 

 peared. 



June 29 and August 7, 1911, the colony was visited to ascertain if 

 the beetles were reproducing, but no evidence was secured. Neither 

 Mr. Harbeson nor the laborers had seen any of the beetles since they 

 were liberated save one dead specimen that was found about June 25. 

 At this time the men were finding both adults and small cutworms of 

 N. clandestina. 



June 6, 1912, 3 males and 6 females that had just been received 

 from Washington, D.C.,were added to the colony, which now totaled 

 10 males and 12 females liberated. The colony was visited several 

 times during the year, namely, February 3, April 8, May 29, June 6, 

 and September 25, and examinations made, but there was no evidence 

 that the beetles reproduced. 



Although reproduction was not noted with any of the beetles in 

 the greenhouse up to the end of 1912, larvse might have been present 

 in small numbers. 



It is not strange that it did not occur or was unnoticed with so 

 few beetles in a large greenhouse. It is demonstrated in the follow- 

 ing paragraph that adults of this species feed upon cutworms during 

 the night when the latter come to the surface of the earth to obtain 

 food, and the writers still have hope that this species may prove a 

 beneficial enemy of cutworms under these conditions. In this case 

 it was possible for the beetles to escape, as the ventilators and 

 doors were frequently left open. 



