ENTOMOLOGICAL SOCIETY 



bine the habits of the earwigs with those of the true Thysanura. 

 It lives among vegetable debris in very moist places, is extremely 

 quick and agile in its movements, is very soft and delicate in tex 

 ture, and is provided witli a pair of long, many-jointed stylets 

 instead of the forceps of the adult earwig. Curiously enough, 

 these are exactly the differences which obtain between Japyx, the 

 only other insect with forceps like the earwig, and the smaller 

 and more thysanuroid analogue of Campodea also found in Liberia 

 and described before this Society in 1899, un der the name Pro 

 japyx * Recently Projapyx has been found to be not uncommon 

 in Porto Rico, and seems always to occur in the same localities 

 as the Porto Rican species of Japyx, that is, in all sorts of situa 

 tions from moist valleys to the tops of dry limestone hills. 



But if Projapyx is really the larva of Japyx, students of the 

 temperate species have failed of their full duty, or else we have 

 found repeated in this orderf the strange conditions of the ear 

 wigs where some species have a larval stage and a metamorphosis 

 which have been suppressed in the others. 



It is realized that this reasoning reverses, for the present case, 

 at least, the opinion held by Lubbock and others that the larval 

 stages of insects are derivative and adaptative, not ancestral 

 and primitive. No reason is, however, apparent why one of 

 these opinions should exclude the other, and in the present in 

 stance it seems obvious that from the standpoint of hexapod 

 structure Dyscritina is much less specialized than the adult earwig, 

 or than the larva of the Hymenoptera or Lepidoptera. 



If, instead of holding that the Dyscritina stage of the earwig 

 is an adaptation, we interpret it as a more primitive condition, 

 it will be necessary to apply the same reasoning to the orthop- 

 terous groups to which the earwigs have been thought to be 

 closely allied. Most of the cockroaches, like most of the earwigs, 

 have no pronounced metamorphosis, but in several genera there 

 is a transformation in both sexes, while in others only the males 

 reach the winged condition. Metamorphosis is more accentuated 

 among the cockroaches than among the remaining orders of 

 Orthoptera, so that the current opinion that these insects are 

 primitive because they have no metamorphoses is self-contra 

 dictory. 



Having thus emancipated ourselves from the notion that the 

 cockroaches represent the primitive insect type, it will be easier 

 to appreciate at its proper value the long-obvious probability 



* Proc. Ent. Soc. Washington, iv. 222, 1899. 



t A separate order Dicellura was established for Japyx in 1896, for the 

 reason that it seemed more remote from the true Thysanura than the 

 latter are from the Orthoptera. See Brandtia, p. 49. July 30, 1896; also 

 Proc. Ent. Soc. Washington, iv, 222, 1899. 



