LeConte.] 



SCOLYTID.E. 343 



mera small, transverse, posterior and intllstinct. Metastenium very long, 

 episterna parallel, ratlier wide; liiad coxie slightly separated. Ventral seg- 

 ments 5; first and second very sh<»rt, together scarcely equal to the thii'd. 

 which is equal to the fourth; fifth a little longer, rounded behind; last dor- 

 sal segment horiz )ntal, partially or completely covered by the elytra, ac- 

 c^rding as the segments are deflexcd or retrac ed. 



Elytra margined and perpendicularly declivous at base, striate, variously 

 prolonged into processes at tip, according to species and sex. Mesonotum 

 strongly carinate. 



Legs short, thighs stout, compressed; tibiaj shorter than the thighs, stoul, 

 unguiculate, marked on the outer side with transverse ridges. Tarsi long, 

 slender, first joint as long or longer than the three following united; fourth 

 joint one-half as long as the third; fifth as long as the joints 2-4 united; 

 claws long, simple, divergent. 



This sub- family is represented in our fauna by a fow species of Platypus 

 found chiefly in the Southern States. The species are cylindrical, and sug- 

 gest a resemblaace to certain Colydlkim, from which, however, they widely 

 depart in structural characters. 



PLATYPUS Herbst. 



In this genus tlie maxillary palpi are large, flat, membranous, 4-jointed, 

 with the joints received one into the other, and the pygidium is almost or 

 entirely covered by the elytra. The sexual differences in the processes of 

 the elytra are such as to make it difficult to construct a table of the species: 



1. Ventral segments with elevations 2. 



" " without elevations 3. 



2. Elevations at the posterior margin of the 



third segment 1. flavicornis 9 . 



Elevations very acute, at the posterior mar- 

 gin of the fourth segment 2. quadridentatus 9- 



3. Prothorax nearly twice as long as wide 3. compositus (5^ 9- 



" one-half longer than wide 4. rugulosus ^f 9- 



" with two large discoidal punctures 1. flavicornis ^J*. 



1. P. flavicornis Chap., Mon. Plat. 154, f 70, rj* 9 : BostrirJu/.s flav. 

 Fabr., Mant. 212; Sp. Ins. i, 67; Ent. Syst. ii, 364; Syst. Kl. ii, 384; Herbst, 

 Kafer, v, 118; Scolytm fiac. Oliv., Ent. 78, 4, pi. 1, f. 1. 



(^. Elytra with the third interspace somewhat elevated and roughened at 

 base; the posterior process of the elytra shorter and less acute; the declivity 

 of the elytra concave near the tip, and the tip itself truncate and feebly 

 emarginate. Ventral segments finely rugose, regularly convex; prothorax 

 with a large puncture each side of the anterior extremity of the short dorsa! 

 impressed line; P. dinciporus Chap., 1. c. 219, f 123, is a variety in which 

 the elytral process is shorter and less prominent. 



9. Elytra with the base of the third interspace lcs> elevated; the poste- 

 rior process longer, more acute, serrate on the outer side. Ventral surface 



