-38- 



Postmarginal longer than siigmal; neck of metathorax short; abdomen oval- 

 rotund ; vertex broad Subgenus Diglochis Thomson. 



Postmarginal shorter than stigmal or equal to it. 

 Abdomen oblong. 



Vertex rounded in the middle, 9 abdomen ovate, convex below, 9 wings 

 often marked with large smoky discs; club of 9 antennae small, 



shorter than pedicel Subgenus Arthrolytus Thomson. 



Vertex acute in the middle Subgenus Dibrachys Thomson. 



Abdomen rotund; cheeks compressed, acute; wings hyaline, postmarginal 

 shorter than stigmal Subgenus Ccelopisthus Thomson. 



Genus METOPON. * 



9 antennae strongly incrassate, sub-clavate; (^ antennae verticillate-pilose 



Subgenus Metopon Walker. 

 9 antennae with the flagellum of equal width throughout, (^' antennas pubescent or 



densely clothed with short hairs; 9 abdomen rotund 



Subgenus Dirhicnus Thomson. 

 {To be continued.) 



Notes on Thelyphonus Lair. 

 By Geo. Marx, m.d. 



There is a gruup among tlie Arthrogastra, to which Latreille has 

 given the name Pedipalpi. This term can be interpreted in two ways, 

 either, the palpi are Hke legs, or the legs are like palpi. ''Palpi brachia 

 (emiilanies" , says Latr., "the palpi resemble arms". If he had intended 

 to introduce this idea into the name, he should have called the group 

 Brachiopalpi. But he was correct in naming it Pedipalpi, for the anterior 

 pair of legs are here functionally no motor organs; but their strucrure 

 and insertion prove that they are the, here retained, 2nd maxillary or 

 labial palpi of the insects, which are transformed in all other Arachnida 

 into leg-like structures with motor functions, giving thus the whole class 

 the characteristic 8 legs, and which arc here exceptionally preserved in 

 their original form. 



While the insertion of the 8 legs in all Arachnidcs is on one plane, 

 either in close apposition or radiating from the sternum, we find in 

 the Pedipalpi ?i\. their sternal surface only 6 coxce surrounding the sternal 

 plate and the insertion of the first pair is at the pleural side and in the 

 upper outer border of the niaxillse. 



The difference in the structure between the anterior and the other 6 

 legs is remarkable. The former are not half as thick, but at least twice 

 as long as the latter. The tibia represents in the other six legs one joint 

 (in Phrynus sometimes two and three) while it has in the front pair — at 

 least in some — 27 to 37 joints, and the tarsus 8, 65, or even as many as 

 85, when it has in the other 3 pair only 3 joints. 



