Oct., '05] ENTOMOLOGICAL NEWS. 253 



allied genus, Sclerobunus^ has the single claw, but there is a 

 spur or branch-claw on each side toward base. Such a branched 

 claw has been found in several other Phalangids in various 

 parts of the world. In the old classifications the Phalangiifd 

 were divided into two groups, differing from each other by 

 several important characters ; one of these was that in the 

 M< costcthi (Laniatores) there were two claws to tarsi three and 

 four, while Mh.z*Plagiostethi (Palpatores) had only a single 

 claw. Now r the discovery of these forms, which by nearly all 

 structural characters belong to the -\fccostcthi, but have a 

 single tarsal claw throughout, provokes discussion as to their 

 systematic position. 



Loman has proposed to elevate these forms into a new sub- 

 order, the Insidiato res ; and calls attention to some new points 

 of difference, especially the peculiar kind of spines on the palpi. 

 Pocock refuses to accept the Insidiatores as equal to the other 

 two suborders, but keeps it as a superfamily in the Mecostcthi. 

 Most of the species of the Insidiatores come from Australia and 

 New Zealand, a few from Madagascar and South Africa, one 

 from Chile, and now three from the northwestern United 

 States. 



The fact that Cyptobnnus, with its simple claws, is but a 

 cavernicolous adaptation of Sclerobunus, with its branched 

 claws, induces me to think that Sclerobunus is not far removed 

 from typical Mecostethi. I would therefore place still less value 

 upon the tarsal claws and consider them as only of generic 

 value, and that the three forms of Insidiatores found in the 

 northwestern States are more nearly related to the other 

 Mi-fosfii/ii of the neighboring regions than they are to the 

 Australian phalangids having a similar claw-structure. Omit- 

 ting the tarsal claws, Sclerobunus and Cyptobunus belong to the 

 family Phalangodid(C, and possibly might form a tribe therein. 



Thorell and Loman have divided the Phalangodida- of Simon 

 into three or more families, but in treating the species of the 

 United States I do not think it advisable for our forms, and 

 doubt if these families will hold good when the phalangid 

 fauna of the world is more fully known to naturalists. 



