NORTH AMERICAN GEOTRUPINAE — HOWDEN 267 



beetles were attracted to horse and cow dung, human feces, dead 

 animals, chicken feathers and entrails, fermenting malt, isoamyl- 

 amine, and butyi*ic and propionic acids. By the use of the last three 

 and other chemicals in traps, adult activity could bo easily plotted. 

 The relative abundance and time of sm^face activity of splendidus as it 

 was indicated by the use of chemical baits is shown in table 4. 



Spector (1943, p. 229) had previously noted the attraction of splen- 

 didus to chicken heads and feathers, while Moennich (1939, p. 156) 

 mentioned finding a specimen of splendidus at Midvale, N. J., feeding 

 on the fungus Clavaria aurea Fries. In North Carolina, splendidus 

 did not seem to be limited to one or two species of fungi but merely 

 utilized what was at hand. 



Despite the omnivorous habits of the adults, fungi were definitely 

 preferred. In September, the freshly emerged males made burrows 4 

 to 6 inches deep under partially decayed fungi. They then took por- 

 tions of the fungi into the burrows, fed, and apparently awaited the 

 approach of a female. From observation, it seemed to me that the 

 female entered the burrows after the males. The males, when con- 

 sidered as a group, emerged a week or so before the females and made 

 their burrows. When the females appeared, single males could be 

 found in a few of the burrows, but never single females. 



Table 4. — Bait used in traps and number of Geotrupes splendidus splendidus 

 Fabricius collected at Raleigh, N. C. 



(First column under month refers to first two weeks, second column to last two 



weeks) 



Chemicals Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Bee. Total 



Propionic acid 101021183000000000053280 35 



n-Butyric acid 200103 30 441000000010 21 4190 81 



Oleic acid 000000010000000000000000 1 



Isoamylamlne 000000044210000000000000 11 



Valeric acid 000000060000000000000000 6 



n-Amyl mercaptan 000000000000000000050000 5 



Pelargonic acid 000000000000000000041000 5 



Ethyl mercaptan 000000000000000000010000 1 



Total 3 1 1 2 4 31 23 11 3 1 1 36 8 3 17 145 



Sex ratio: 66 males, 79 females. 



In an attempt to learn more about the habits of the adults during the 

 fall, several gallon-cans were filled with dirt, sunk into the ground, and 

 fungi placed on top. When the burrows were noted in the dirt the 

 cans were pulled out, rapidly inverted, and dumped out. In this way 

 several pairs of splendidus were observed in copulation. The male 

 genitalia, when in the process of retraction, was rotated a full 360° 

 to the right. At no time was the genital capsule seen, apparently 

 never being extruded. On Oct. 23, 1950, a pair of splendidus left for 



