THE GENUS CALOSOMA. 101 



HIBERNATION. 



One pair of beetles entered hibernation August 30 and emerged 

 May 17 and 26, 1910, and the average date of entering for 10 adults 

 in 1910 was August 1 . Only one pair of these beetles lived, and they 

 emerged May 15, 1911. During normal seasons in Massachusetts 

 this species enters hibernation during the first half of August and 

 emerges between April 15 and May 15. 



The average depth in the ground to which these beetles go to 

 hibernate is about 2 inches. 



THE EGG. 



The egg is white. ^ Measurements of 12 fresh eggs in 1910 gave an average length 

 of 5.8 mm. and a width of 2.5 mm. The adults of C. calidum are much smaller than 

 scrutator or sycophanta, but the eggs run somewhat larger than those of either 

 species. They have the same general form (elliptical) as those of the species just 

 mentioned and taper slightly toward one end. 



The average number of days required to hatch 59 eggs deposited 

 by one female between June 15 and June 28, 1909, was 4 J. The 

 temperature at that time was very favorable for the acceleration of 

 hatching, the maximum ranging between 80° and 90° F. One hun- 

 dred and ninety-nine fertile eggs deposited by several females be- 

 tween May 22 and August 2 required an average of nine days to 

 hatch. Most of the deposition took place during the month of June, 

 and nine days is about the normal time spent in the egg stage by 

 this species. 



DESCRIPTION OF LARVA.i 



First stage (PI. XVIII, A, B). — Length, 8 mm.; width, 2 mm. at third thoracic 

 segment. Form ellipsoidal, tapering more gradually toward the last segment than 

 in the corresponding stage of C. frigidum. General color of the body and mouth 

 parts dull black, not shining. Head large, as long as wide, dorsal surface flattened; 

 alpi prominent, longer than antennae. Posterior margin of the head somewhat 

 _,marginate at the center. First thoracic segment as long as the two following, slightly 

 wider than the head and edges produced laterally. All the body segments except 

 the last are truncate behind, and bear a prominent impressed dorsal line. Caudal 

 appendages present, simple, and provided with numerous spines. 



Ventral portion of the body nearly pure white r but it is profusely covered with small 

 black chitinous plates. Spiracles nine, black, circular, and arranged just below the 

 lateral edges of the dorsal plates. Anal proleg moderately stout. After feeding for 

 a week the larvae molted. 



Second stage (PI. XVIII, C, D). — Soon after molting the larvae become black and 

 measure 18 mm. in length. Body somewhat stouter than in preceding stage. Head 

 longer than wide, emarginate behind. Prothorax wider than the head. Dorsal line 

 quite prominent. Abdominal segments truncate and slightly produced laterally. 

 ~ r, he second molt occurred at the end of a week. 



Third stage (PI. XIX, A, B). — The following description was not made until the 

 larva was almost ready to pupate. Length, 30 mm. Color, dull black. Head of 

 medium size, flattened, truncate behind. Clypeus slightly broader in front than in 

 \ frigidum. Strongly bilobed. Suture between clypeus and epicranium subobso- 

 lete. ' Mandibles stout, the large tooth near the base being deeply cleft on the inner 

 margin. Prothorax longer than the head, the hind angles slightly curved. Meso- 

 and meta-thorax smaller, but similar in shape, each thoracic segment bearing four 

 pairs of hairs on the dorsal plate. The abdominal plates one to seven of the same 

 form and bearing a moderate carina near the posterior edge of the segment. Eighth 

 segment a little larger, slightly wider, and also bearing a carina, lateral edges of each 

 abdominal segment bearing three short hairs. The last segment small, posterior 

 angles produced backward, but hind edge of segment truncate; caudal appendages 

 long, blunt, spiny, slightly depressed, and bearing on the upper surface a hump-like 

 protuberance provided with a few spines. The spiracles are nine in number, and are 



1 Burgess, A. F. Notes on certain Coleoptera known to attack the gypsy moth. In 44th Ann. Rpt. 

 Mass. State Bd. Agr. f. 1896, p. 412-431 (p. 426-428), pi. 3-5, 1896. 



