JUAN VINAS—THE REVENTAZON VALLEY 223 



Of the beetles (Coleoptera) which we found on the canon 

 side the largest and most striking was the Harlequin beetle 

 {Acrocinus longimanus) , well known in tropical America. 

 Its larva, a thick white grub, bores into rubber trees and 

 probably others also. It owes its name of "Harlequin" 

 beetle to the bizarre markings, red, black and gray, of its 

 elytra or wing-covers. Its front legs are immensely long, 

 (14 cm. or 5.6 inches) and also the antennae (15 cm., 6 inches) 

 as compared to the length of the body (6.5 cm., 2.6 inches). 

 Moreover the tibia of these legs is quite sharply bent whereby 

 the grasping power is greatly increased. These peculiarities 

 are alluded to in its specific name, longimanus. We found 

 one lying on its back in the road on July 28 and kept it alive 

 several weeks but were unable to induce it to eat anything. 

 When we picked it up it produced a rasping sound resembling 

 a file drawn over wood. On the middle line of the front part 

 of the mesothorax is a patch of highly polished black chitin, 

 which under the lens shows very fine cross-wise ridges or 

 teeth. The back of the prothorax rubs over these ridges 

 and so produces the rasping. On August 12 we photographed 

 this beetle. During a previous attempt it bit A.'s finger 

 but no ill consequences followed. On both occasions the 

 beetle was exceedingly restless. On August 25 we chlo- 

 roformed it and found many external parasites. Most of 

 these were mites, several hundred in number, representing 

 two species of Uropoda (clavisetosa and bisetosa) described 

 by Mr. Banks as new. They were most abundant between 

 the elytra and wings but were also on the upper surface 

 of the body between the pro- and mesothorax. Two pseudo- 

 scorpions {Chelanops nodulimanus) were on the upper side 

 of the abdomen below the wings, resting on a small silken 

 web as wide as the abdomen, which presumably they had 

 spun. A third pseudoscorpion was found on the cotton hold- 

 ing the chloroform and probably came from the same place. 



