Mr. F. P. Pascoe on some new Genera of Curculionide. 427 
insect here described from the two well-known species of Arach- 
nobas, which, though somewhat similar in general outline, are so 
different in other respects as scarcely to suggest any affinity between 
them. 
Thyestetha nitida. (Pl. XVII. fig. 20.) 
T. subelliptica, nigra, nitida, glabra; capite fronte convexo, impunctato, 
inter oculos rude punctato; rostro ferrugineo, subtiliter punctato, 
utrinque basi albo-squamoso; antennis ferrugineis; prothorace fere 
- conico, lateribus leviter rotundato, vage punctato, pone oculos squamis 
albis tecto ; elytris rufis, basi prothorace haud latioribus, seriatim punc- 
tatis, seriebus distantibus, punctis distinctis, pone medium gracile 
attenuatis, apice conjunctim rotundatis; corpore infra albo-squamoso ; 
pedibus nigris, disperse albo-squamosis; tarsis ferrugineis. Long. 
- 22 lin, 
ab. Aru. 
Opoacis. 
Characteres ut in Mecopo, sed clava antennarum art. basali brevi; pedes 
antici mediocres, coxee propriz spina acuta armate; femora postica 
longissima, incrassata, haud linearia; elytra prothorace latiora; pro- 
pectus maris muticum ; et core postice valde distantes. 
The great length of the anterior legs of the male is the most 
striking feature in Mecopus, while in this genus the posterior legs, 
or rather thighs, almost as long as the insect itself, are nearly as 
remarkable. It is very curious to notice that the two spines arising 
from the breast, just in front of the anterior cox, in Mecopus, are 
in Odoacis attached to the coxz themselves. 
Odoacis grallarius. (PI. XVII, fig. 24.) 
O. elliptico-ovatus, depressiusculus, ater, squamis ochraceis parce ad- 
spersis ; rostro subtiliter punctato, infra oculos ad medium tricarinulato ; 
oculis intus late emarginatis; antennis ferrugineis, nitidis; prothorace 
antice in medio carinato, angulis posticis acutis, emarginatis, dorso 
crebre foveato, foveis squamositate ochracea indutis ; scutello obovato, 
postice latiore; elytris lateribus antice parallelis, dein sensim angus- 
tatis, apice conjunctim rotundatis, dorso basi subdepressis, rugoso- 
sulcatis, parce ochraceo-squamosis, lateribus profunde foveato-sulcatis, 
angulis anticis dentibus quinque vel sex instructis ; corpore infra nigro, 
sternis foveatis, ochraceo-squamosis; pedibus nigris, squamositate 
ochracea tectis; femoribus posticis apice et tibiis dimidio basali, 
nigris, glabris; tibiis posticis brevibus, curvatis, compressis. Long. 
23-6 lin. 
Hab. Siam. 
SEmio. 
Rostrum modice elongatum, subarcuatum, apicem versus paulo depressum ; 
scrobe brevissima, recta, laterali, oculum desinente. Oculi rotundati, 
