94 BULLETIN ill, V. S. DEPAKTMENT OF AGRICULTURE. 



CALOSOMA HAYDENI Horn. 



[PI. XVII, B.\ 

 ORIGINAL DESCRIPTION. 



The above name is proposed for a species in which the first three joints of the anterior 

 tarsi of the male are spongy pubescent beneath, the base of the thorax truncate. It is 

 therefore allied to oxk triste and obsoletmn, but differing from them in having the elytra 

 connate and body apterous. The head is large, as in triste, and the frontal impressions 

 deep, rather finely punctiu-ed and wrinkled; vertex with but few punctures, occiput 

 smooth. Thorax as in triste, but with the basal impression deeper and the lateral 

 margins at base more strongly reflexed, nearly as much as in semilaeve. Disc with 

 distinct coriaceous sculpture and feeble median line, margins coarsely but distantly 

 punctm'ed, becoming more dense near the hind angles and basal region. Elytra 

 elongate oval, humeri strongly rounded, and as distinctly margined as the sides. 

 Surface very convex in both directions and with striae of fine distinct punctures 

 feebly impressed. Basal region with distant submuricate punctures. Margins dis- 

 tinctly muricately punctured, more dense at the humeral region, almost disappearing 

 at the apex. Metathoracic parapleurae and sides of abdomen with coarse punctm-es. 

 Its color above and beneath is shining black. 



Length 0.84 inch; 22 mm. 



Collected in southern Colorado by C. Thomas, of the U. S. Geological Survey, under 

 Dr. F. V. Hayden. 



DISTRIBUTION. 



This species was described by Dr. Horn in 1870.^ The type speci- 

 men was collected in southern Colorado. There are also other later 

 reports of its being taken in Colorado, Arizona, and New Mexico. 



COLLECTIONS AND SHIPMENTS. 



The data included on this species were secured in New Mexico by 

 members of the scientific staff under the Cereal and Forage Insect 

 Investigations of this Bureau in connection with the New Mexico 

 Range Caterpillar {Hemileuca oliviae Ckil.). Mr. D. J. Caffrey with 

 the assistance of others conducted the life-history studies and through 

 the late Prof. F. M. Webster and Mr. W. R. Walton, the notes were 

 secured for pubUcation here. 



October 16, 1915, there were received at Melrose Highlands, Mass., 

 from Mr. Caffrey at MaxweU, N. Mex., 7 males and 5 females, living. 

 These were packed in damp sphagnum moss and arrived in good 

 condition. They were placed in battery jars and fed larvae of P. 

 rapae. One pair remained more or less active until November 2 in 

 Massachusetts and consumed 22 of the above larvae before entering 

 hibernation. Thev are stiU in hibernation at this writing (Aprif, 

 1916). 



FOOD CONSUMED BY ADULTS. 



July 28, 1913, 2 males and 1 female were collected in the field and 

 enclosed in a battery jar. They were offered plenty of H. oliviae 

 larvae and pupae during the season of which they consumed 114 of the 

 larvae up to September 13. They were offered the pupae after this 

 date but refused. Weather conditions changed to cold and windy 

 and the beetles sought hibernation soon after. In another jar con- 

 taining the same number of adults, 102 Hemileuca larvae and no pupae 

 were consumed. The beetles in cages in 1914 proved predacious on 

 H. oliviae larvae and fed from June 8 to September 3, the number 

 destroyed each day gradually decreasing until toward the end of 



» Trans, Amer, Ent. Soc, Vol, 3, 1870, p. 69. 



