NORTH AMERICAN GEOTRUPINAE — HOWDEN 243 



to become fully pigmented and hardened. About the fifth day 

 after metamorphosis the adults became active, emerging from their 

 cells in late September and early October. 



The adults fed and overwintered in theu- feeding burrows. The 

 following spring the females dug and provisioned the brood cells, 

 unaided by the males. 



Description of the larva of Geotrupes hlackhurnii hlackhurnii is 

 based on the following material: 20 third instar exuviae with adults, 

 10 third-stage larvae, and 2 second-stage larvae, all collected during 

 the summer of 1951 at Faison, N. C, by P. O. Ritcher and H. Howden; 

 23 pupae with third instar exuviae, 24 third-stage, 5 second-stage, 4 

 first-stage larvae, and 5 eggs, all from adults in cage at Raleigh, N. C, 

 by H. Howden; third instar exuvia with adult collected at Mills River, 

 N. C, by H. Howden. 



The larvae of the eastern subspecies of hlackhurnii appear to differ 

 only slightly from Ritcher 's description (1947, pp. 6-7) of the larvae 

 of G. hlackhurnii, which I have referred to the western subspecies, 

 G. hlackhurnii excrementi. The only structures not consistent with 

 Ritcher's excellent description were noted in the hypopharynx and 

 glossa (pi. 8, fig. 2). The asymmetrical oncyli differed slightly in shape 

 from the western subspecies excrementi. Also, the setae in front of the 

 hypopharyngeal oncyli and behind the transverse row of sensilla have 

 their origin much nearer to the midline than do the outermost sensilla. 

 Other than that, there were no consistent dift'erences noted. Maximum 

 width of head capsule was 3.9 to 4.5 mm. 



The egg of G. hlackhurnii hlackhurnii (pi. 14, fig. 2) is yellowish white, 

 generally oval with one end larger than the other. The egg increases 

 gradually in size until a maximum size of 3.8 to 4.0 mm. in length 

 and 2.3 to 2.5 mm. in width is reached a day or so before hatching. 



First instar maximum width of head capsule is 2.4 to 2.6 mm. Struc- 

 turally, larva differs very little from third instar. The respiratory 

 plates of the first instar are very small and circular, while in the 

 second- and third-stage larvae they are large and crescent-shaped. 

 Also, the antennal segments of the first instar vary slightly in length 

 and the mandibular teeth are more pronounced than in later stages. 

 Posterior portion of abdomen not swollen as in second and third instar. 



Second instar maximum width of head capsule is 3.4 to 3.7 mm. 

 Structurally it is very similar in all respects to third instar. 



Specimens examined: 259 males, 237 females. 



CONNECTICUT: 2 males, 1 female. Hartford, Pomfret, Yalesville; (1) April, 

 (1) October. 



GEORGIA: 18 males, 13 females. Armuchee, Atlanta, Clarkston, Head River, 

 Morgan, Newton, Panthersville, Rome, Satolah, Savannah, Spring Creek 

 (Decatur County), Stone Mountain, Summerville, Thomasville; (1) January, 



