THE GENUS CALOSOMA. 23 



spring of 1912. Pair No. 5097 produced 15 fertile eggs between 

 June 1 and July 1. Copulation was noted June 1, 9, and 11, and the 

 female died August 3. Female No. 5062 and female No. 5841 each 

 deposited infertile eggs, which were not counted. The eggs were 

 deposited June 7 to July 2, and one of the females died August 6, 

 while the other entered hibernation August 30. 



This species, like some of the other species of Calosoma experimented 

 with at the laboratory, reproduced sparingly in jars. The same was 

 true of C. inquisitor, C. auropunctatum, and G. wilcoxi. 



LONGEVITY. 



The one male and three females that emerged from hibernation in 

 the spring of 1912 were* collected in Washington, D. C, in the spring 

 of 1911. All of these adults died in July and August, 1912, which 

 indicates that the species lives at least two full years in the adult 

 stage, as the beetles in question were larvae and pupae in the summer 

 of 1910 or earlier and died in the summer of 1912. Three years is 

 probably nearer the age limit of the species under natural conditions. 



HIBERNATION. 



All the beetles received from various sources in 1909 and 1910 died 

 the same season without entering hibernation. Several adults, how- 

 ever, that were received during the spring and summer of 1911 ceased 

 activity and entered hibernation August 12 and 26 and September 5. 

 The same beetles emerged in the spring of 1912 on May 27 and 28 and 

 June 3. The cavities, so far as could be determined, ranged from 1 to 

 3 inches deep. Three males and four females entered hibernation in 

 the fall of 1911 and one male and three females emerged the following 

 spring. 



Adults of this species hibernated successfully at Melrose Highlands, 

 Mass., through the winter of 1911-12, one of the most severe in this 

 section for many years, which proves their hardiness when food and 

 other conditions are favorable. 



THE EGG. 



Ten fresh eggs gave the following average measurements: Length, 5.4 mm.; width, 

 2.5 mm. They are somewhat elliptical in form with a slight taper toward one end. 

 The color is white with a faint yellowish tinge. They vary greatly in form, ranging 

 from long and almost cylindrical, tapering slightly at both ends, to short, oval, and 

 somewhat kidney-shaped. 



About 100 eggs were deposited by three females in 1912 but only 



12 of these hatched. The fertile eggs were deposited June 4, 5, and 

 12, and 8 to 13 days were required for hatching. These records indi- 

 cate that 8 or 9 days is the average time the eggs require for hatching 

 during June. 



DESCRIPTION OF LARVA. 



First stage. — Form short, stout. Average length of 7 specimens, 7.7 mm.; width, 

 2.9 mm. Caudal appendages straight, very long (2.5 mm.), slender, bearing numerous 

 short spines. Color black above, ventral plates dark to grayish-brown. 



Second stage. — Form short, very broad. Average length of four alcoholic specimens, 



13 mm. ; width, 4 mm. Caudal appendages very long, the same length as in first stage 

 but somewhat larger. Protuberance small, located about one-half the distance from 

 base to tip. Ends of tergites, viewed from ventral side in partially fed larvae, project- 

 ing well laterad, posterior angles of same obtuse and projecting prominently backward. 

 Posterior angles of last segment short, rather acute. Color same as in first stage. 



