— 205 — 



Geoirupidoe and Copridce, with, however, strong tendency towards the 

 Dynastide group of Scarab, pleuroslicti. 



This new group is characterized under the name Pleocomini in 1861 

 (Classification of the Coleoptera of North America, p. 123 and 128) and 

 in the " List of the Coleoptera of North America," published in 1863, at 

 p. 37 is placed among the Scai-abceidce laparostuti between the groups 

 "Geolrupini" and " Acanthocerini." * At last, in 1874, (Note on the 

 genus Pleocoma, Lee, in Tr. Am. Ent. Soc. V, p. 81-84) Leconte gives 

 a resume ol his statements made in his earlier publications on the genus 

 mentions the two species, Pleocoma stuff, and hirticol/is, described in 1870 

 by Schaufuss (Nunquam otiosus II, p. 50) and now first makes known, 

 what is of die highest importance, the true female of the genus. This is 

 considerably larger than the male, oval and strongly convex, furnished 

 with elytra but without wings, with stronger legs, and short tarsi, not 

 more than one-third the length of the tibiae. The prolongation of the 

 head is short and broad, not emarginate nor bifurcate, the frontal horn is 

 short, the thorax closely punctured, and not indented : the antennae are 

 much smaller with smaller, rounded club. Before proceeding to a de- 

 scription of the four species known to him (P. fimbriata ^, Behrensh (J 

 9, hirtkollis <$ Q> and Edwardsii $) Leconte mentions having re- 

 ceived a larva from Mr. Behrens, found deep in the earth, and described 

 and figured by Osten-Sacken in an appendix to this paper (Description ol 

 the larva of Pleocoma, Lee, by Baron R. Osten-Sacken). Of this larva 

 Leconte says that it justifies the erection of a special group for this genus 

 and that its characters fully confirm the opinion already expressed regard- 

 ing the relations of the genus. 



At all events from these five publications of Leconte it sufficiently 

 appears that the systematic position of the genus caused him in the earlier 

 years a considerable amount of thought. Only after he had during five 

 undergone considerable changes of opinion did he arrive at a defi- 

 nite, and afterward repeatedly confirmed conclusion. The, at first, "ap- 

 parently Dynasti-form " genus changed tq him next to a middle thing 

 between the Dynastini 'and Geotrypim, then to the representative of a special 

 group to be placed between the Coprini and Geotrypini, and still later the 

 Dynastini and Coprini are dropped altogether, and the special group Pleo- 

 comini figures among the ScarabcBtdce laparoslicti between the Geotrypim 

 and Trogini. 



To tin; latter conclusion, which seems to have become fixed with Le- 

 conte, it is obvious that only the following train of thought can have led 

 him :— The Geotrypim are the only known Lamellicornes possessing eleven 

 jointed antennas; therefore this genus Pleocoma which also possesses 

 ■■■ The same position is retained in the 2nd Ed. of the "Classification" 1883.- J. U.S. 

 Entomologica Americana. Vol. hi. 32 Fi bbi aky 1888. 



