MONOCKEPIDIUS. 347 



The numerous examples from the above Mexican localities agree well with a specimen 

 of M. athoides from Arizona, communicated by Dr. Horn ; they vary greatly in size — 

 from 10-14 millim. in length, and from 2J-4 millim. in width. They have the antennae 

 rather short in both sexes ; the thorax convex, closely, uniformly punctate, and with 

 the hind angles bicarinate ; the elytra rather deeply punctate-striate, the interstices 

 somewhat convex, and thickly, subrugosely punctate ; the fourth tarsal joint narrowly 

 lamellate beneath. The two specimens in the Janson collection from that of Candeze 

 are labelled M. parallelus. 



13. Monocrepidius angusticollis. (Tab. XV. fig. 11, s .) 



Very elongate, depressed, slightly shining ; brown or reddish-brown, paler beneath, the hind angles of the 

 prothorax and the antennae ferrugineo-testaceous, the legs testaceous; clothed with fine yellowish- 

 cinereous hairs. Head thickly, finely punctate, declivous in front ; the frontal carina broadly subtruncate 

 and moderately prominent; antennae slender, about reaching the basal fourth of the elytra, joint 3 nearly 

 twice as long as 2, the two together slightly longer than 4. Prothorax narrow, subparallel, about one- 

 fourth longer than wide, feebly longitudinally convex ; the hind angles acute, narrow, greatly produced, 

 abruptly divergent, slightly upturned, not carinate ; the surface thickly, finely punctate, and with a 

 smooth raised median line towards the base. Elytra nearly four times the length of, and one-half wider 

 than, the prothorax, depressed, the sides subparallel to the middle, and very gradually converging thence 

 to the apex, the apices conjointly rounded ; finely and rather sharply punctate-striate, the interstices flat, 

 feebly transversely rugulose. Beneath closely and finely, the prosternum more coarsely and sparsely, 

 punctate. Posterior coxal plates very broadly dilated to near the middle, abruptly and obliquely 

 narrowing outwards. Fourth tarsal joint with a short lamella beneath. 



Length 11-11|, breadth 3 millim. ( tf .) 



HaJb. Mexico, Ciudad in Durango 8100 feet (Forrer). 



Two male examples. This species is perhaps nearest allied to M. parallelus ; it 

 differs from all the allied forms in its very narrow, subparallel thorax, the hind angles 

 of which are long, slender, abruptly divaricate, and without distinct carina ; the elytra 

 are depressed, very little narrower at the apex than at the base ; the penultimate joint 

 of the tarsi is feebly lamellate beneath. 



14. Monocrepidius apiatus. 



Monocrepidius apiatus, Er. Archiv fur Naturg. xiii. 1, p. 78 1 ; Cand. Monogr. Elat. ii. p. 223, t. 4. 

 fig.3 2 . 



Hah. Panama, Bugaba in Chiriqui {Champion). — South America 2 to Peru 1 2 . 



Six specimens. This species agrees with M. pilatei in having the terminal dorsal 

 segment (the apex only of which is usually visible) sharply, longitudinally sulcate down 

 the middle in both sexes. In the closely allied M. nocturnus and M. notatus there is 

 no trace of this groove. 



2Y2 



