292 HETEROMERA. 
** Species apterous. 
6. Tarpela durangoensis. 
Oblong ovate, moderately convex, dark brownish-bronze, slightly shining. Head shallowly impressed in front, 
the epistoma distinctly arcuate emarginate, coarsely, very closely, and confluently punctured; eyes com- 
paratively large; antenne rather short, the third joint not twice the length of the second, the three 
outer joints wider and equal in length, 9 and 10 subtriangular, piceous, the basal joint lighter ; prothorax 
transversely convex, broader than long, the sides slightly and about equally narrowed before and behind 
the middle, feebly sinuate before the base, and narrowly but very distinctly margined, the anterior angles 
broadly and very strongly produced in front and a little rounded, the hind angles subrectangular, the base 
very feebly bisinuate, almost straight in the middle, the basal foves almost obsolete, the surface punctured 
like the head but with the punctures rather more regular and not so frequently confinent ; seutellum 
transverse, sparingly punctured ; elytra distinctly wider than the prothorax, subtruncate at the base, the 
sides straight in front, a little rounded beyond, slightly transversely swollen in the middle, deeply 
punctate-striate throughout, the scutellar stria deep, the punctures oblong in form, rather coarse, and 
closely placed, the interstices convex and almost smooth ; tibie roughly and closely punctured, the femora 
smoother ; the entire surface beneath (including the flanks of the prothorax) coarsely and closely punc- 
tured, the punctures here and there longitudinally confluent at the sides; prosternum rounded off and 
declivous, the apex not produced; mesosternum rather deeply excavate. Body apterous. 
Length 7 millim.; breadth 33 millim. ( 2.) 
Hab. Mexico, Ciudad in Durango 8100 feet (orrer). 
A single example. 
7. Tarpela corpulenta, (Tab. XII. fig. 23.) 
Oblong ovate, strongly convex, dark brownish-bronze, slightly shining. Head very coarsely, closely, and con- 
fluently punctured, broadly flattened in front, the epistoma distinctly emarginate, the usual transverse 
impression very shallow; eyes small; antenne short, slightly passing the base of the prothorax, rather 
stout, widening outwardly, the third joint not twice the length of the second, the penultimate joints sub- 
triangular, the apical joint longer than the tenth; prothorax very narrowly margined, strongly longitu- 
nally convex, broader than long, the sides rounded about the middle, very slightly and somewhat obliquely 
(not sinuously) narrowing behind, and more distinctly narrowing and rather strongly sinuate anteriorly, 
the anterior angles very strongly and subacutely produced in front, the base very feebly bisinuate (almost 
straight), the basal fovece nearly obsolete, the hind angles subrectangular, the surface very closely and 
coarsely punctured, the punctures here and there longitudinally or sinuously confluent ; elytra strongly 
convex, subtruncate, and slightly wider than the prothorax at the base, a little rounded at the sides, 
deeply punctate-striate throughout, the sutural stria deep, the punctures oblong in form, rather 
coarse, and somewhat closely placed, the interstices convex and almost smooth; legs short, closely and 
coarsely punctured, the femora smoother ; the entire surface beneath (including the flanks of the pro- 
thorax) coarsely and closely punctured ; prosternum declivous, the apex not produced ; mesosternum very 
narrow, feebly excavate. Body apterous. 
Length 63-73 millim. ; breadth 3-33 millim. ( 9.) 
Hab. Mexico, Ventanas in Durango (Hoge). 
Three female examples. This apterous species will be at once known from TZ. duran- 
goensis by its very convex form, small eyes, the sides of the thorax sinuate in front (the 
anterior angles in consequence narrower and more acute), &c.; it is allied also to the 
Texan Helops farctus, Leconte (placed in Nautes by Allard), but is very much smaller 
and narrower than that apterous insect. 
