254 GEO. H. HORN, M. P. 



by a metasternal prolongation or an intercoxal process of the first 

 abdominal segment. 



I do not understand why M. Abeille has omitted Adelops {Bathy- 

 scia), and Aphaobius from the above table. They cannot constitute a 

 separate tribe or even group, but should be placed : Bath/scia after 

 Pholeiion, and Aphaobius after On/o(us, the regularly oval form sepa- 

 rating both of the genera from those to which they are otherwise 

 related by their tarsal characters. 



The second group Platycholei contains but one genus. 



FLATYCHOLEUS n. g. 



Form oval, depressed. Head suddenly contracted behind the eyes, occipital 

 ridge indicated by a fine line. Eyes small, transverse to the axis of the head. 

 Antennae attaining the hind margin of the thorax, slender, gradually thickened 

 externally, eighth joint a little narrower and shorter than the ninth. Last 

 joint of maxillary palpi slender, conical, much narrower than the preceding 

 and scarcely half as long, the third joint stout, conical and truncate at apex, 

 second joint slender. Middle coxae separated by the mesosternum which is 

 obtusely elevated. Posterior coxae separated by a broadly triangular process 

 of the first abdominal segment. Tarsi slender, the first three joints of the 

 anterior and the first two of the middle dilated in the males; hind tarsi with 

 the first joint longer than the next three together. Tibiae not spinulose exter- 

 nally, tip with small spurs and fimbriate with unequal spinules. 



The mesosternum separates the coxae rather more widely than in 

 Ptomaphagns and is not earinate but forms an obtuse ridge. The 

 head is not provided with an occipital ridge, so that it is more deeply 

 retractile, while in all the other genera in which the head is suddenly 

 narrowed behind the eyes, the occipital ridge is received against the 

 apical margin of the thorax. 



P. leptinoides Crotch, {Ptomaphagvs). — Rather broadly oval, wider in 

 front, depressed, testaceous, moderately shining, sparsely clothed with short 

 luteous pubescence. Head very sparsely and finely punctulate. Thorax more 

 than twice as wide as long, wider than the elytra, apex emarginate, sides 

 strongly arcuate, broadest a little in front of base, rapidly arcuately narrowing- 

 to apex, base broadly emarginate, hind angles rectangular, surface shining, 

 very sparsely punctulate. Elytra narrower than the thorax, humeri oblique, 

 sides arcuately narrowing to tip, surface moderately densely punctate, sutural 

 stria wanting. Body beneath sparsely punctate. Length .12 inch; 3 mm. 

 (PI. VI, fig. 2). 



This species has considerable resemblance in facies to Leptinus. 

 It is totally unlike any of the species of the tribe. In both sexes 

 the middle tibiae are arcuate, in the males the anterior tibiae are 

 broader at apical half, recalling the form of the tibiae in certain 

 tStelidota. 



Occurs in northeastern Calilbrnia and western Nevada. 



