COLFOPTERA. 367 



There also they copulate, one of the sexes being without and sus- 

 pended in air(l). In the 



Xyletinus, Lat. Ptilinus, Fab. 



To which we will unite the Ochina of Ziegler and Dejean, the 

 antennae are simply serrated in both sexes(2). 



Dorcatoma, Herbst.,Fab. 



The antennae consisting of but nine joints, terminating suddenly 

 in three larger ones; the two penultimate joints resembling the teeth 

 of a saw(3). 



Anobium, Fab., Oliv. Ptinus, Lin. Byrrhus, Geoff. 



The antennae also terminated by three larger or longer joints, but 

 the two penultimates are in the form of a reversed and elongated cone, 

 and that of the end is oval or nearly cylindrical; they consist of 

 eleven joints. 



Several species of this genus inhabit the interior of our houses, 

 where, in their larva state, they are very noxious, attacking the tim- 

 bers, furniture, books, Sec. and piercing little round holes in them 

 similar to those made by a very small gimblet. Their excrements 

 form those little pulverulent piles of wood-dust which are frequently 

 observed on floors. The larvae of other species of Anobium attack 

 flour, wafers, cabinets of Birds, Insects, Sec. 



Both sexes, in the nuptial season, frequently summon each other 

 by reiterated and rapid strokes of their mandibles against the wood 

 they inhabit, and mutually answering the signal. Such is the cause 

 of that noise, resembling the accelerated tick of a watch, which is 

 so often heard and which is superstitiously called the death-watch. 



JL. tesselatum, Fab.; Oliv., Col. II, 16, i, 1. Three lines in 

 length; dead dusky brown, with yellowish spots formed by hairs; 

 thorax smooth; elytra not striated. 



A. pertinax; Ptinus pertinax, L. ; Jl. striatum, Fab. ; Oliv. lb. 

 I, 4. Blackish; thorax with a yellowish spot at each posterior 

 angle, and near the middle of its base a compressed eminence 



(1) Ptilinus pectinicornis, Fab. ; Oliv., Col., II, 17, bis, 1, 1; P.pectinatus, Fab.; 

 P. serratus, Id.; Ptinus denticornis, var. ; Panz., lb. VI, 9; XXXV, 9. 



(2) Ptilinus pallens, Germ.; Ptinus serricornis, Fab. In the Ochina licderse, the 

 antennae are somewhat larger than those of the Xyletini, rather less serrated, the 

 second and third joints almost equal in length. I have not examined the other 

 species of Ochinx mentioned by Count Dejean in his Catalogue. 



(3) Dorcatoma dresdensis, Herbst., Col. IV, xxxix, 8. 



