228 PROCEEDINGS OF THE NATIONAL MUSEUM vol. io4 



Genus Geotrupes Latreille 



Geoirupes LatreiUe, 1796, p. 6; 1802, pp. 142-144; 1804, pp. 142-147; 1806, pp. 

 91-95; 1810, p. 428; 1829, pp. 542-546.— Kirbj^ 1818, p. 461.— Mulsant, 

 1842, pp. 353-367.— Jekel, 1865, pp. 513-618.— Horn, 1868, pp. 313-322, 

 1880, pp. 139-154.— LeConte and Horn, 1883, p. 243.— Blanchard, 1888, 

 pp. 103-110.— Boucomont, 1902, pp. 1-10; 1906, pp. 1-44; 1911, pp. 344- 

 345; 1912, pp. 19-33.— Dawson, 1922, pp. 195-197.— Blatchley, 1910, pp. 

 938-939; 1928, pp. 44-45.— Bradley, 1944, p. 112.— Ritcher, 1947, pp. 1-27.— 

 Potts, 1948, pp. 23-26; 1951, pp. 49-51.— Townes and Howden, 1952, pp. 

 207-209. 



Geotrupes Fabricius (not Latreille), 1798, pp. 1-7. — Walckenaer, 1802, p. 1. 



Scarabaeus Linn6, 1758, pp. 345-354.— Fabricius, 1775, p. 17; 1798, pp. 23-34.— 

 Olivier, 1789, pp. 55-69.— Marshara, 1802, p. 8. 



Genotype: Scarabaeus stercorarius Linne designated by Latreille 

 (1810, p. 428) (see opinion 11 of the International Commission of 

 Zoological Nomenclatm-e) . If this designation is not acceptable to 

 some investigators, then Curtis' designation (1829, page opposite 

 pi. 266) of stercorarius Limie should be. There has been some doubt 

 concerning the application of the name Geotrupes, but I believe the 

 above usage is correct. For a full discussion of the problems involved, 

 consult Potts (1951) and Townes and Howden (1952). 



Generic limitations: Given by Latreille (1796, p. 6): 



Antennes de onze articles. Levre superieure avanc6e. Mandibules fortes. 

 Lfevre inf^rieure a deux divisions along^es. 



C. H. chaperon rhomboidal. ficusson. Jambes ant^rieures dentel^es. 



Other useful characteristics, besides the 11-segmented antennae, 

 are general oval body shape, antennal club 3-segmented, small, not 

 convex on both sides, eyes divided by canthus, color dark iridescent 

 blue or green to dark brown or black, front femur with conspicuous 

 hairy spot on anterior internal surface, elytra usually striate, thorax 

 similar in both sexes, mid- and hind tibiae with apical transverse 

 carina complete. 



In addition to the characters mentioned above, many males of the 

 species of Geotrupes exhibit striking external modifications. These 

 sexual differences have caused a number of investigators to propose 

 subgeneric groupings for the various species. Many of these groupings 

 appear justified but others contain a rather unrelated mixture of 

 structm^ally different species. 



It is in this category of unrelated species that many of the North 

 American species seem to fall. The subgenera Cnemotrupes Jekel 

 (type Qeotrupes blackburnii Fabricius) and Onychotrupes Jekel (type 

 Geotrupes splendidus Fabricius) are separated only on the basis of an 

 enlarged middle tarsal claw in the males of the latter. In other 

 morphological respects Geotrupes splendidus is closely related to G. 

 blackburnii, while G. ulkei Blanchard and Q. egeriei Germar, both in 



