THE GENUS CALOSOMA. 113 



oval in form without regular marginal notches. Posterior median plates rectangular 

 in form and outer ventral plates on third to seventh abdominal segments oval. Pos- 

 terior angles of anal segment broad at base, acute at tip, projecting slightly upward. 



LARVAL RECORDS. 



Many larvae were reared in individual jars during 1914 which were 

 fed mostly on N. clandestina and M. americana larvae. Those reared 

 hatched May 8, 11, 22, and 24 and ceased feeding between June 9 

 and 15. The larvae that hatched late in May matured in much 

 shorter time — 18 to 22 days, while those that hatched early in May 

 required about one month. One and sometimes two large cater- 

 pillars were consumed by one beetle larva each day excepting during 

 the molting periods, or a total of from 20 to 35 before maturity. 

 Proportionately more would be destroyed if small caterpillars were 

 offered. 



Time spent in the larval stages for a few specimens averaged as 

 follows : For first, 5 days ; for second, 6 days, and for the third about 

 9 to 12 days to the date larvae cease feeding for making cavity. 

 About 4 days additional is passed in the cavity before pupation. 



HABITS OF THE LARVAE. 



A first-stage larva put on the bark of a white oak post, after several 

 tumbles reached the top (6 feet). Each time placed on with head 

 upward, it would turn the opposite direction and descend, several 

 times circling the post. Third-stage larvae showed about the same 

 inclination to reach the ground when placed upon the post. They 

 were not able to ascend more than three feet before falling. 



The slowness and awkwardness with which these larvae handle 

 themselves on trees indicated that their natural habits are similar 

 to those of C. calidum Fab., that is, remaining always on or near the 

 ground in search of food. 



PUPA. 



Two pupae (1 male and 1 female) were preserved in alcohol from 

 the rearings of P914, the average measurements of which were 18.2 

 mm. in length and 7.3 mm. in width. June 20, 1 pupa was unearthed 

 from a cavity at the bottom of a jar which was then about 5 days 

 old, as determined from the colorations of the tarsi, eyes, and buccal 

 parts. The color of the pupa as a whole grew darker daily until it 

 died June 25. It is probable that about 10 to 12 days are required 

 to pass the pupal stage for this species. 



BIBLIOGRAPHY. 



1829. Eschscholtz, J. F., Zoologischer Atlas enhaltend Abbildungen neuer Thier- 

 arten wahrend Kotzehue's, etc. Part I, Taf. XXV, p. 23. 

 Original description of Calosoma canccllatum. 



1854. LeConte, J. L., Descriptions of some new Coleoptera from Oregon, collected 

 by Dr. J. G. Cooper, of the North Pacific R. R. Expedition. Proc. Acad. Nat. 

 Sci. Phila., T. 7, p. 16. 

 Description of C. aenescens from Fort Vancouver; comparison is made with Calosoma tepidum 

 and calidum. 



1857. LeConte, J. L., Report upon Insects Collected on the Survey (Coleoptera), 

 p. 30. 



Redescription of Calosoma cancellatum with a citing of the original description by Eschscholtz,. 

 Also a note that C. aenescens was collected in Sacramento, California.. 



54880°— Bull. 417—17 & 



