April, 1919 Bulletin of the Brooklyn Entomological Society. 39 
ing their plant-inhabiting stages, while internal “parasites” of 
plants form the great majority of holometabolous insects. He 
likewise considers that in the greater part of holometabolous in- 
sects, the most primitive representatives of the group have ligni- 
vorous larvee, or at least larve resembling lignivorous larve in 
structure. Lameere believes that holometabolism had a mono- 
phyletic origin—in other words, that is occurs only in one group 
of insects and the forms descended from them. 
In discussing Lameere’s view, we again come upon the old 
question of whether such a feature of external environment as 
life in plant tissue, could produce metamorphosis. I think not! 
I should be much more inclined to consider that bodily changes 
(and habits also) were first produced (under the normal sur- 
roundings of the primitive winged insects) and the insects in which 
they occurred were thereby enabled to enter upon a wood-boring 
life. Furthermore, I would be inclined to look for a “ fore- 
shadowing” of the adaptations which would enable an insect to 
enter upon a wood-boring existence, in the tendency for many 
primtive insects to hide under stones and other protected places. 
We find even in the Thysanura, a well developed tendency to 
hide under stones, etc., and the same hiding tendency occurs 
among the Symphyla, and “ Myriopoda” in general, as well as in 
certain Crustacea which are related to insects (Lygia, Oniscus, 
etc.), so that it must have occurred at an early period in insectan 
development, if this has any meaning. Even in certain Blattide, 
Grylloblattide, Gryllidz and other primitive insects this tendency 
to hide under stones also occurs, and in the group which I con- 
sider as representing as nearly as any the condition ancestral to 
the “ Neuropteroid” insects, there is a widespread tendency to 
hide under stones or shelter of some kind, as is done by the 
Dermaptera, Embiidz, lower Coleoptera (Lampyride, etc.), ete. 
The Plecoptera themselves (7. e., the forms near the base of the 
ancestral group) show an unmistakable tendency to hide in the 
adult stages, while their aquatic immature forms are found under 
stones in the water. Similarly many other primitive water-in- 
habiting immature stages, such as those of Ephemerids, etc., 
occur under stones, and the larve of the most primitive repre- 
sentatives of the holometabolous insects such as the Neuroptera, 
