PHYLOGENY OF THE NEMOCERA. 265 



coxse, femora and tibiae. Two British species (Cryptops) have 

 short, stiff hairs regularly disposed over the legs; but a larger 

 and broader species with a greater number of legs has them 

 almost bare. 



In Blatta a few short hairs are scattered over the limbs, but the 

 femora and tibiae are armed with many strong, sharp spines, 

 which, in the genus Phyllodromio, are serrated with minute but 

 regular barbs, undoubtedly specialized for raptorial purposes. 

 In Forficula there are no bristles, only minute, soft scattered 

 pubescence, which is much thicker on the inner side of the tarsi 

 than elsewhere. In Panorpa a short, very even, uniformly 

 long and regular pubescence is found studded with longer spines 

 on the tibiae and tarsi, and with tibial spurs of a curious and 

 marked structure, each spur appearing as if it were made up of a 

 number of fine hairs of various length, so that the edges appear 

 almost plumose, certainly serrate. 1 



It may be of interest to record that Peripatus novazcalandiiz, 

 that remarkable survival, has neither pubescence nor bristles on 

 its short forelegs or on any part of the skin, which, however, is 

 studded with minute papillae. 



All these arthropods except Peripatus have one character in 

 common, and that a very marked one. From the upper joints, 

 or femora to the claw or claws, there is seen what under low r 

 magnification appears to be a thread-like tendon, but under high 

 magnification a duct leading to the claw, either carrying poison 

 to the claw or moistening the plate at the base of the empodium, 

 and from that part the pulvilli. This duct might have been 

 described from diptera instead of Blatta, Fotficnla or Panorpa so 

 obvious are the homologies, but the arrangement of hair and 

 bristles on the surface suggests no counterpart, except in Panorpa. 

 A comparison of my preparations in the Nemocera with that 



1 In my paper on the systematic affinities of the Phoridae in the Transactions 

 of the Entomological Society, I stated that this structure was only to be found in 

 the Mycetophilidae and Phoridae. I should have stated that only in the former 

 family were they found in a size comparable and requiring a magnification of 250 

 diameters for elucidation. These on Panorpa and the diptera mentioned later 

 are much larger and can be seen with lower powers, except in the case of the Rhy- 

 phidae, which is a recent observation. Of course the presence of this structure in 

 other insects admittedly of ancient type only strengthens my former argument, 

 but it also shows the danger of dogmatic formulas. 



