404 PROCEEDINGS OF THE NATIONAL MUSEUM vol. in 



but sparsely punctured forming longitudinal wrinkles laterally, except 

 two apical segments on which punctures are very fine and more 

 closely spaced. Male genitalia with ventral portion of lateral lobes 

 continued backward as a single spine (pi. 4, fig. 26). No apparent 

 external sexual dimorphism. Measm-ements : length 5.7-7.4 mm.; 

 width 3.0-3.8 mm. 



Remarks. — This species is very closely allied to P. americanum 

 and at fii-st appeared to represent just a slightly aberrant form of 

 the latter species. Champion was apparently unfamiliar with P. 

 americanum except from its description, but he correctly inferred the 

 close affinity between it and the present species, a tribute to the ac- 

 curate descriptions of Laporte and Brull^. 



P. mexicanum may be distinguished from P. americanum by the 

 relative flatness and feebly shining lustre of the dorsum, the much 

 less conspicuous punctures on the head, pronotum, and elytra, and 

 the form and punctation of the lateral margins of the pronotum. All 

 of the foregoing characters, relative in nature, give, when taken to- 

 gether, a facies totally unlike that of any other member of this species 

 group. 



Type: BMNH: Jalapa, Mexico (Hoge). Lectotype selected from 

 Champion's cotypic series; sex undertermined. This is the specimen 

 figured by Champion. It is in excellent condition, but because of 

 its historical value and the manner in which it is mounted, it was 

 deemed inadvisable to attempt a dissection. 



Specimens examined. — From the following locahties, 84: 



United States: Arizona (Chiricahua Mts., Flagstaff, Palmerlee, Santa Cata- 

 lina Mts., White Mts.). New Mexico (Las Vegas, Porvcnir). 



Mexico: Ciudad in Durango, Durango, Jalapa, Juan Manuel El Salto, Mount 

 Colima. 



Platydema neglectum, new species 



Description. — Body obovate, strongly convex, light reddish brown 

 to almost black, strongly shining. Head prominently impressed be- 

 tween eyes, coarsely and densely punctured, antennae and mouth- 

 parts reddish brown, apical antennal segment sometimes sharply 

 pointed (pi. 6, fig. 54); terminal segment of maxillary palpus elongate, 

 narrowly triangular; eyes large, flattened dorsally, separated ven- 

 trally by a distance usually subequal to longer axis of one eye. Pro- 

 notum trapezoidal, sides usually almost straight, narrowly margined, 

 strongly reflected, bead very fine, basal angles nearly square, apical 

 angles obtuse, narrowly rounded, surface coarsely but not densely 

 punctured, lateral punctures slightly larger than those of disc. Elyt- 

 ral striae moderately strongly impressed, punctures rather coarse and 

 deep, intervals convex, rather coarsely and densely punctate. Pro- 



