FIc. 
EXPLANATION OF PLATE XXII. 
Oryctes rhinoceros. 
1.—Mouthparts of larva from below, with left maxilla 
removed and turned over to show supposed stridula- 
tory structures. 
2.—Pupa from above showing stridulating organs. 
3.—Left anterior stridulating organ of pupa more highly 
magnified. 
4.—Posterior end of abdomen of adult, with left elytron 
removed, showing the ridges with the aid of which 
the insect appears to stridulate. 
Adoretus spp. 
5.—Mouthparts of A. versutus—the labrum slightly raised, 
the mandibles widely and maxillae more moderately 
opened, 
6.—Mouthparts of A. lasiopygus—the labrum removed, the 
mandibles and maxillae very widely opened to show 
the molar teeth of the former. This figure is more 
highly magnified than the last. 
