252 ENTOMOLOGICAL NEWS. [June, 'l6 



Platyptera to Euplatyptera, in referring to the Embiid group. 

 As was mentioned above, the Termites occupy a position 

 somewhat intermediate between the Grylloblattid-Embiid- 

 Perlid group and the Blattidae, and in many respects, they ap- 

 proach very closely to, or parallel the Blattoid line, in their 

 phylogenetic development. I have been unable to study such 

 primitive Termites as Mastotermes, but I feel certain that 

 these will show marked affinities with the Grylloblattid-Embiid- 

 Perlid group, since those Termites which I have been able to 

 examine all indicate a close relationship to this group, and I 

 think that the Termitid line leads back to the Perlid rather 

 than to the Blattid line of development, as is indicated in the 

 diagram. As will be discussed later on, the Blattid and Perlid 

 lines ultimately approach each other quite closely, so that the 

 resemblances of the Termites to the Blattids may possibly be 

 explained as the retention in both lines, of characters inherited 

 from the common ancestral group from which sprang the an- 

 cestors of the Blattids, Termites and Perlids. The affinities 

 of the Termites to the Blattid group may, on the other hand, 

 be much closer than is indicated in the diagram ; but this 

 point can be definitely determined only upon the examination 

 of the most primitive representatives of the Termitid group, 

 which are not at present accessible to me. Since this group 

 froms a distinct order, the term Isoptcra should be applied to 

 it. Although I have been unable to obtain specimens of the 

 rare order Zoraptera, described by Silvestri, I would judge 

 from the figures of these insects, that they form an off-shoot 

 from the main Termite stem, and have departed but little 

 from the rest of the Termitoid group. 



Since the Perlid line of development is approached or is 

 paralleled by so many other lines of descent, it forms one of 

 L he most important of the lower groups of winged insects, the 

 only other lower group which rivals it in this particular being 

 the Phasmid group. The Perlids as a whole are as primitive 

 as any winged insects, and, with the Blattids, must be regarded 

 as the nearest living representatives of the ancestral winged 

 insects, since the group as a whole is as little modified as any 

 known winged forms. The nearest relatives of the Perlids 



