240 A YEAR OF COSTA RICAN NATURAL HISTORY 



optera, Diptera); Arachnids: 6 species (of 6 genera, of 4 

 families, of 4 orders, Scorpioni, Pseudoscorpioni, Phalangida, 

 Acarina) ; Annelids: I species. 



Of the beetles which we found in bromeliads at Juan Vifias 

 the most interesting in structure was the carabid Pachyteles 

 seriatoporus, because of its possessing, on its first pair of 

 legs, organs suggesting the antenna cleaner of the bees and 

 ants. In the latter two this organ is formed by the tibia 

 and first section of the tarsus of the first leg, the first tarsal 

 joint bearing a semicircular notch lined with a row of stiff 

 hairs, while at the tip of the tibia is a spine which holds the 

 antenna in place as it is being drawn through the tarsal notch. 

 In Pachyteles seriatoporus the semicircular notch is located at 

 mid-length of the tibia and is bounded by a grooved and 

 pointed process of the under surface; the grooved floor of 

 the notch runs obliquely across the tibia and is smooth and 

 polished on its forward end while its hind edge is guarded 

 with a row of close-set, short hairs. On the under surface 

 of the femur at mid-length is a strong, slightly curved, 

 tapering, sharp spine, so placed that when the tibia is flexed 

 upon the femur the spine of the latter would guide the an- 

 tenna and hold it from slipping out as it was drawn through 

 the tibial notch. ^ P. seriatoporus is three-fifths inches 

 (15 mm.) long, uniform shining brown in color, and has an- 

 tennal joints 5-10 almost square, 1-4 and 11 more elon- 

 gated. 



The Costa Rican naturalist, Seiior C. Picado, has published 

 in Paris (1913) a thorough and detailed study of the epiphy- 

 tic bromeliads and their fauna. He groups the members 



^ Prof. L. C. Miall has recorded in his Natural History of Aquatic Insects (second 

 edition, London, 1903, pp. 376-378) some observations and experiments by Mr. W. 

 F. Baker showing that many Carabidae possess and use a similar antenna-cleaner. 

 No spine on the femur, such as we describe for P. seriatoporus, is mentioned, how- 

 ever. 



