THE GENUS CAJLOSOMA. 



69 



males were received from Europe and placed in the jars. Fourth to 

 sixth stage caterpillars of Euproctis chrysorrhoza and Porthetria dispar 

 were supplied. After the males were added, June 23, the average 

 per day for each beetle was two sixth-stage gipsy-moth caterpillars. 

 Feeding records were kept in 1909 of four pairs of beetles which 

 were received from Europe in 1908, and the results secured are 

 indicative that the species is a ravenous caterpillar hunter, as in one 

 case a pair destroyed as many or more large caterpillars in a season 

 than is normally killed by Calosoma scrutator or C. sycophanta. 



Table 17. — Feeding record of four pairs of Calosoma reticulatum, 1909. 



Pair 

 No. 



Feeding 

 record 

 started. 



Ceased 

 feeding. 



Milacosoma 



americana 



third to 



sixth 



stages. 



Porthetria 

 dispar, 

 sixth 

 stage. 



Total. 



1504. . . 

 1506. . . 

 1508. . . 

 1593... 



iMay 27 

 May 14 

 i June 3 

 May 15 



2 July 2 

 Aug. 13 

 2 July 7 

 2 July 21 



159 

 504 

 196 

 297 



10 

 24 



18 

 65 



169 

 528 

 214 

 362 



1 Females fed on steak 8 to 10 days before records were started. 

 £ Females died a few days later. 



It will be noted from Table 17 that these beetles are voracious 

 feeders. The average number of caterpillars consumed by each of 

 the four pairs was 343 for the season of 1909. All of the females 

 except No. 1508 reproduced. The average number of caterpillars 

 consumed per day during the feeding season for pair No. 1508 was 

 seven, and the average for the four pairs during the time each fed 

 was six. 



Pair No. 1506 lived to emerge from hibernation in the spring of 

 1910 and fed until July 2 before the female died. Two hundred and 

 fourteen fifth and sixth stage caterpillars of Noctua clandestina, 

 Malacosoma americana, and Porthetria dispar were consumed by the 

 pair between April 27 and July 2, 1910. The pair reproduced in 

 1909 and 1910, which accounts for the large amount of food con- 

 sumed each year. 



Two pairs of beetles reared in the laboratory vivarium issued as 

 adults in July, 1909, and came to the surface of the earth in the jars. 

 Five sixth-stage caterpillars of Porthetria dispar were consumed by 

 one pair and 13 by the other. All these beetles died during the 

 latter part of July and the first half of August of the same j^ear. 

 This same habit of coining to the surface and feeding almost imme- 

 diately after issuance as adults has been noted in the case of Calosoma 

 calidum, but the beetles often died before the following spring. 



REPRODUCTION. 



Many specimens that were received from Europe in 1908 were kept 

 in jars and cages for reproduction during the summer, but these did 

 not reproduce until 1909 and 1910. Four females received in June, 

 1908, reproduced as follows in 1909: The first female deposited 39 

 fertile eggs between June 7 and 28 and died July 6; the second, 71 

 fertile eggs between June 14 and June 27, then ceased feeding and 

 entered hibernation August 18; the third, 20 fertile eggs between 



