NORTH AMERICAN GEOTRUPINAE — HOWDEN 239 



which is rather elongate, curved toward the midline, and extended 

 beyond the basal tip of the wide left paramere 



Variation within the species is considerable. Size, punctures, 

 degree of sexual modification in the males and, to some degree, color 

 show wide differences, even in specimens from the same colony. 



The description of the male has been largely made from a homotype 

 from Raleigh, N. C, compared with the Fabrician specimens 

 for me by S, L. Tuxen of the Copenhagen Zoological Museum. 



The species may be distinguished by the male genitalia (pi. 4, 

 figs. 4, 5), the shape of the longitudinal carina of the foretibia (pi. 2, 

 fig. 10), the conical teeth on the underside of the foretibia of the males, 

 poorly punctured elytral striae, and shining black color, sometimes 

 with a coppery cast. 



Geotrwpes blackburnii blackburnii was by far the most common 

 species of Geotrupes taken by me in North Carolina. During the fall, 

 winter, and early spring specimens were numerous under cow dung. 

 Addiction to cow dung was not very noticeable however, as specimens 

 were frequently taken at carrion, almost any type of dung, chicken 

 feathers, and decaying fungi. On one occasion several specimens 

 were taken on the bare gi'ound under a willow tree badly infested with 

 aphids, but whether they were attracted by the ''honey dew" or not 

 cannot be stated. 



One of the easiest and best methods for collecting the adults, as it 

 eliminated digging, was by the use of chemical attractants and fer- 

 menting malt. Not only were many adults collected by the use of 

 attractants, but the time and amount of above-ground activity of 

 the adult beetles could easily be traced through their use. These 

 data, with the chemicals that proved useful, are given in table 3. 



The greatest feeding activity was in the fall just after the emergence 

 of the adults. The time of mating was not definitely ascertained, 

 but as several pairs were taken in burrows 4 to 8 inches deep under 

 cow dung in October, copulation may have occurred then. The 

 adults were not only active during the spring and fall, but several 

 times were also seen flying in the late afternoons or early evenings 

 of warm winter days. Quite frequently specimens were taken at 

 lights on warm nights, particularly during the winter. About 9 p. m. 

 on Jan. 6, 1953, I found several male blackburnii at brightly lighted 

 store windows. 



Because of an ample supply of adults, rearing was attempted in 

 several ways. Specimens were put in gallon cans partially filled with 

 dirt and supplied with fresh cow dung. Others were put in an apple 

 box filled with dirt and covered with a wire screen. Outdoors, in a 

 shaded spot, an enclosure 3 feet wide by 8 feet long was made and 

 covered with a wire screen. About 50 males and 50 females were put 



