110 



BULLETIN 417. U. S. DEPARTMENT OF AGRICULTURE. 



The average number of days passed in the egg stage was 9, for 111 

 eggs observed in 1910. Fifteen days were required for hatching eggs 

 deposited the latter part of May, when the weather was cool, but 

 only three to six days were necessary late in June or early in July. 



DESCRIPTION OF LARVA. 



First stage. — Medium to small size, fusiform. Average length of 12 specimens, 

 9 mm.; width. 2.2 mm. Caudal appendages long, straight, bearing a few long spines. 

 Color shining black above, ventral plates grayish-brown. 



Second stage. — Somewhat - stouter than first stage. Average length of nine speci- 

 mens, 16.5 mm.; width, 3.5 mm. Caudal appendages stout at base, rather erect to 

 dorsal protuberance, curved slightly upward and gradually tapering beyond pro- 

 tuberance. Protuberance short, erect, and located less than one-half the distance 

 from base to tip. Color same as in first stage above, ventral plates dark brown. 



Third stage. — Rather robust in form. Average length of four specimens, 22 mm.; 

 width. 4.9 mm. Caudal appendages short, stout, and rather erect to dorsal protuber- 

 ance, curved upward beyond this, acute at end. Protuberance more prominent than 

 in second stage. Color of dorsum shining black with metallic luster, ventral plates 

 dark brown. No reddish-brown patch at base of caudal appendages in second or 

 thud stages. 



TIME REQUIRED TO COMPLETE LARVAL STAGES. 



From 3 to 7 days are required for the first stage, or an average of 

 5; 3 to 5, or an average of 4, for the second; and 10 to 14, or an 

 average of 11, for the third. The larvae are active and feed about 19 

 or 20 days. Four days are passed in the prepupal stage. 



Table 26. — Food required to mature larvae of Cdlosoma auropunctatum, 1910. 







Malaco- 



PortJic- 









soma 



tria 





Xo. 



Date 

 hatched. 



ameri- 



■cana 



eaten, 



sixth 



stage. 



dispar 



eaten, 



fourth to 



sixth 



stages. 



Total. 



2789-A 



June 11 



5 



16 



21 



2789-B 



Ml 







40 



45 



27S9-C 



13 



3 



13 



16 



27n9-H 



14 



6 



46 



52 



27S9-I 



13 



4 



51 



55 



27S9-J. 



U6 



1 



oo 



56 



1 Larva? died when full grown. 



The average number of large caterpillars required to complete the 

 growth of 12 larvae, 6 of which are given in Table 26, was 40. 

 The larvae of this species appear to be very voracious feeders, as from 

 16 to 56 large caterpillars were destroyed. The average for this spe- 

 cies was twice that consumed by larvae of Calosoma calidum. 



Two larvae of this lot pupated and issued as females in July, 1910. 

 They came on the surface of the earth and ate 19 and 27 large cater- 

 pillars, respectively, before entering hibernation. These are the only 

 adults that have been reared and indicates that this habit may be 

 constant. This species resembles 0. calidum in this respect. 



PUPA. 



Length of female, 19 mm.; width, 7.5 mm. Male, 18.7 mm. long, 

 7.2 mm. wide. 



The larvae under observation in 1910 ceased feeding June 27 to 

 July 3, then entered the earth and constructed cavities. Pupation 



