*0F THE 



AMERICAN ENTOMOLOGICAL SOCIETY. 



FOLHME VII. 



Bfotes on some species of HISTER. 



BY GEORGE H. HORN, M. D. 



In the synopsis of the species of Hister of our fauna published by 

 me (Proe. Am. Philos. Soc. 1873, p. 280), the arrangement is very 

 nearly that adopted by Marseul, except that the truncation of the 

 mesosternum enters as an important factor. There was observed at 

 the time (p. 292), a tendency in several species in which the meso- 

 sternum was emarginate to have the emargination become so feeble as 

 to cause the character to lose a portion of its value. In a review of 

 the species made while comparing some unnamed specimens it seemed 

 that sufficient importance had not been given to the striation of the 

 presternum, a character casually mentioned by Marseul but not other- 

 wise made use of. 



A modification of the table (synopsis p. 280), introducing this char- 

 acter seems to give a much better arrangement of the species, at the 

 same time rendering the transition between the normal Histers and 

 Phelister less abrupt. In the latter group all the species have a striate 

 prosternum. The following is in short the change proposed: 



Prosterniim convex, without striae. 



Mesosternum emarginate Groups 1 — 7. 



Mesosternum truncate Groups 8 — 9. 



Prosternum more or less flattened, bistriate. 



Mesosternum very feebly emarginate Group servus. 



Group — servus. 

 Prosternum more or less flattened and bistriate, anterior tibige tri- 

 dentate, the apical tooth bifid. (Elytra with four entire striae and no 

 subhumeral). The species are as follows: 



Outer thoracic stria entire. 



Pygidium coarsely and densely punctured servuS. 



Pygidium finely and sparsely punctured indistincttis. 



Outer thoracic stria very short deiectus. 



TRANS. AMER. ENT. SOC. VII. (1) JANUARY, 1878. 



