OEA. 605 



surface thickly clothed with, very fine, pallid, sericeous pubescence, the elytra also with scattered intermixed 

 longer hairs. Head very minutely punctate ; antennae as in 0. obliqua ; prothorax short, rapidly 

 narrowing from the base, explanate and acutely margined at the sides, minutely punctulate ; scutellum 

 punctured like the prothorax ; elytra explanate and acutely margined at the sides, densely, very finely 

 punctate, with intermixed slightly coarser punctures, and indications of an impressed line near the suture. 



$ . Fifth ventral segment arcuate-emarginate at the apex. 



Var. &. The discoidal vitta of the elytra obliterated or reduced to a narrow streak, the elytra sometimes with 

 irregularly scattered brownish spots. 



Var. (3. Above and beneath, the legs, and antennae testaceous, the head, prothorax, scutellum, and posterior 

 knees brown or reddish-brown ; the elytra as in a. 



Length 4|-5, breadth 2§-3| millim. 



Hab. Mexico, Cordova, Vera Cruz {Salle), Jalapa (Hoge) ; Guatemala, near the city 

 (Salvin), Duefias (Champion) ; Honduras (Mus. Brit.). 



Found in abundance in all its varieties upon a species of Salix at Duenas ; also not 

 uncommonly at Jalapa. In many of the pallid examples the elytra are spotted with 

 brown, this being due to the irregular distribution of the darker pigment. 0. discoidea 

 is closely allied to 0. obliqua, but differs from it in having the elytra a little less 

 explanate at the sides (the general shape being rather more elliptic), and not so 

 minutely punctured, with the intermixed coarser punctures not very distinct. In 

 0. obliqua the elytral punctuation is very minute, and the intermixed coarser punctures 

 quite distinct. A specimen from Duenas is figured. 



4. Or a marmorata. 



Broad-oval, depressed, shining ; pale testaceous, the prothorax with indistinct brownish markings, the elytra 

 with numerous irregular brown spots which are here and there coalescent, the posterior femora suffused 

 with reddish-brown at the apex ; the upper surface thickly clothed with fine pallid pubescence, the elytra 

 also with intermixed longer hairs. Head, prothorax, and scutellum closely, very minutely punctate ; 

 antennae moderately long and slender, joints 2 and 3 short, equal in length, 4-11 elongate ; prothorax 

 short, rapidly narrowing from the base, explanate and acutely margined at the sides ; elytra acutely 

 margined and slightly explanate at the sides, closely, very minutely punctate, with intermixed slightly 

 coarser punctures, and indications of an impressed line near the suture. 



Var. The elytral markings obliterated. 



Length 4-4i, breadth 2|-3 millim. 



Hab. Panama, Volcan de Chiriqui, David (Champion). 



Two examples, both somewhat immature. Very near 0. obliqua, but differing from 

 it in the less explanate margins of the elytra, as well as in colour. The punctuation 

 of the elytra is equally minute. From 0. discoidea it may be separated by the distinctly 

 more finely punctured elytra. The elytral markings in the typical form somewhat 

 resemble those of certain varieties of 0. discoidea, but the spots are much more 

 numerous and partly coalescent. 



5. Ora mixta. (Tab. XXVI. fig. 27.) 



Broad-oval, short, depressed, rather shining ; black or pitchy-black, the sides of the head in front and the 

 anterior and lateral margins of the prothorax obscure testaceous ; the elytra with an oblong humeral 



