DERMAPTERA SALTATORIA. 51 



Genus 10. OPOMALA. 



The American species form three groups. The first is represented hy 

 bivittata, viridis, filiforrais, vittata and femoralis. 



The second group is limited to cylindrodes, aud is distinguished from 

 the first by the broad i'astigium. 



The third also includes one species and is distinguished from the first 

 and from the second by the structure of the prothorax, which has a keel 

 and becomes narrower in front. It hardly belongs to this genus. 



In Africa there is one group which resembles the secoud American 

 group as regards the fasligium, but has a keeled prothorax. 0. basalis 

 and O. inteiiineata are varieties of one species. 



In Asia there are two types. The first, including convergens and 

 tarsalis, corresponds wilh the first American group. The second, repre- 

 sented by semipicta and galeata, agrees with the African form. 



The Australasian O. inornata agrees with the third American group 

 in the prothorax, which tapers towards the head, but does not recede so 

 much as that species from the typical form of the genus. 



In Australia the first group, represented by O. sordida, comes nearest 

 to the Australasian species, but the prothorax is keeled and is less narrowed 

 in front. 



The second group includes amaena, brevitibia and brevicoruis, and 

 corresponds to the first American group. 



Picta, cingulata and serrata, whose habitat is unknown, agree with the 

 African form. 



The following species is referred with doubt to this genus :— 



Mas. Corpus gracillimum, fere cylindricum. Caput productum, 

 subpunctatum ; fastigium subcarinatum, triangulare ; frons dense punctata, 

 valde retracla. Oculi obliqui, non prominuli. Antennae graciles, subplaua?, 

 fere filiformes, prothorace paullo longiores. Prothorax dense punctatus, 

 postice vix latescens, margine postico valde rotundato. Prosterni spina 

 crassa, transversa, obtusa. Abdomen compressum. Femora postica 

 abdomine multo breviora. Alae anticse angustae, corpore multo breviores. 



Male. Body very slender, uearly cylindrical. Head elongate, slightly 

 punctured; tip of the vertex flat, triangular, with a slight keel; front 

 thickly punctured, very much retracted; four distinct keels, diverging 

 towards the face. Eyes elongate-oval, oblique, not promiuent. Antenna? 

 slender, nearly filiform, slightly flattened, a little longer thau the protborax. 

 Prothorax thickly punctured, hardly widening hindward; transverse 

 impressed lines slightly marked; fore border slightly rounded; sides 

 straight; hind border much rounded. Prosternal spiue thick, transverse, 

 obtuse at the tip. Abdomen compressed. Hind femora much shorter than 

 the abdomen ; hind tibiae a little shorter than the hind femora. Fore 

 wings narrow, much shorter than the body. 



Opomala? Syrica. 



Mas. Fulva ; vertex albidus,piceo autfulvo lineolatus ; antennce pallide 

 lutea; alee anlicce albidie, pallido venosce. 



