THE GENUS CALOSOMA. 



59 



is not as hardy a species as sycoplianta or the species of Calosoma 

 native to New England. At any rate the chances of it having become 

 established in this country are very small. 



THE EGG. 



The egg is yellowish- white, elliptical, usually tapering toward one end. Twelve 

 fresh eggs gave the following average measurements : Length, 4.3 mm. ; width, 2.4 mm. 



Seventy-nine eggs were deposited by one female between May 24 

 and June 10, 1911, and these required an average of 9.6 days to 

 hatch. Seventy-one eggs were deposited by six females in 1911 

 between June 1 and June 27 and averaged 6£ days in the egg stage. 

 The difference in time noted above was due to the temperature, as 

 high temperature favors rapid hatching. 



BRIEF DESCRIPTION OF LARVA. 



First stage. — Color brownish-black above, ventral plates brownish-gray. Form 

 slender. Average length of 12 specimens, 8.9 mm.; width, 2.3 mm. Caudal 

 appendages of medium length, rather slender. 



Second stage. — Color brown to dark brown above; ventral plates chestnut brown. 

 More slender than first stage. Average length of 12 specimens, 12.6 mm.; width, 

 2.9 mm. Caudal appendages stouter but no longer than in first stage. 



Third stage. — Body more robust than in previous stages. Average length of 12 

 specimens, 21 mm.; width, 4.5 mm. Posterior angles of anal segment acute and 

 extending backward rather prominently. Caudal appendage stout, almost straight; 

 dorsal protuberance prominent, erect, located about two-thirds distance from base to 

 tip. Color same as in second stage. A reddish-brown patch at base of caudal append- 

 ages in second and third stages. 



LENGTH OF TIME REQUIRED TO COMPLETE LARVAL STAGES. 



Observations were made on 14 larvae during the summer of 1910 

 to determine the length of time passed in each stage. The average 

 for the first stage was 8.6, for the second 6.6, and for the third 8.7 

 days to the date the larvae ceased feeding. Twenty-four days 

 covered the active growing period of the larvae. The time passed in 

 the first stage may appear somewhat long as compared with records 

 of other species, but the weather was cool during the first part of 

 June and retarded the growth and activity of the larvae. 



FOOD CONSUMED BY LARVJE. 



Twenty-two feeding experiments with larvae were started in indi- 

 vidual jars during the summer of 1910 and from these 14 complete 

 records were secured, as shown in Table 14. 





Table 14. — Food eaten by larv 



se of Calosoma inquisitor. 1910. 









1 

 Malaco- 









Malaco- 











soma 



Porthe- 









soma 



Porthe- 









ameri- 



tria dis- 









arneri- 



tria dis- 





No. 



Date, 

 hatched. 



cana 

 caterpil- 

 lars eaten, 

 fourth to 

 sixth 

 stages. 



par cater- 

 pillars 

 eaten, 



fourth to 

 sixth 

 stages. 



Total. 



No. 



Date, 

 hatched. 



cana 

 caterpil- 

 lars eaten, 

 fourth to 

 sixth 

 stages. 



par cater- 

 pillars 

 eaten, 



fourth to 

 sixth 

 stages. 



Total. 



2721-A i 



June 1 



5 



18 



23 



2721-M 



June 3 



5 



16 



21 



3721-B 



1 



5 



7 



12 



2721-P 



4 



4 



8 



12 



2721-C 



1 



6 



7 



13 



2721-Q 



4 



4 



4 



8 



2721-E 



1 



2 



10 



12 



2721-R 



5 



4 



14 



18 



2721-F 



3 



8 



6 



14 



2721-S 



5 



10 



13 



23 



2721-G 



3 



7 



7 



14 



2721-U 



5 



5 



8 



13 



2721-1 



3 



7 



19 



26 



2721-V i 



6 



8 



9 



17 



Full-grown larvae died. 



