54 THE ENTOMOLOGIST. 



and external anatomy, and their various modifications for pro- 

 tective and defensive purposes. Not only have we here a great 

 gathering of facts from various sources, but they are treated and 

 marshalled by the author with much philosophical insight, and 

 with the addition of new material of his own, and obviously very 

 frequently a verification by actual observation of the facts quoted 

 from other authorities. 



The discussion of Dyar's work on larval tubercles, and of 

 Packard's tabulation of the forms into which they are modified, 

 will be very useful to those who are unable to study the scattered 

 papers in which these are published, and will be materially 

 assisted by the critical views of the author. 



The discussion of the meaning and use of the special structure 

 of the geometrous larva states some interesting and, I think, 

 original views of the author, which appear to be so conformable 

 to the facts that they may be provisionally accepted. He points 

 out that the Geometer as a tree-feeder is specially fitted to travel 

 quickly, and so shorten the periods during which it loses by 

 movement its protection by resemblance to a twig, mid-rib, &c. 

 The tree-feeders amongst the Sphinges, Saturnids, &c, obtain 

 their protection by moving with extreme slowness, as well as by 

 terrifying attitudes, &c. The young Noctua larvae that are 

 geometrous are shown to have very similar necessities to the 

 tree-feeding Geometers, and have independently made an ap- 

 proach to the same structure. 



We altogether miss any serious account of the imaginal 

 structure, and there is little or no reference to neuration. 

 Though the author nowhere gives a hint to that effect, we con- 

 clude that these will form the subject of the general chapters in 

 some future volume. The materials to be collated and philoso- 

 phically considered are still no doubt meagre ; Bodine, Keuter, 

 Jordan, and others are, however, getting series of facts together. 

 Neuration, which has held systematists so largely its worshippers, 

 has had no formal treatment since Spuler's investigations, until 

 Comstock and Grote's more recent monographs. Still, for 

 practical classificatory purposes, a large mass of information 

 seems to be in the hands of many persons who tell us nothing, 

 except what we can gather from the use they make of it. A 

 comprehensive essay on the subject is much to be desired. Our 

 author's silence is perhaps to be interpreted as the result of a 

 desire to give a rest to an overworked aspect of his subject. 

 The great value of this part of the work is that it brings together 

 in readable form a mass of information only to be got from a 

 multitude of different sources. The same feature marks equally 

 the rest of the work dealing with families and species. It involves 

 a great mass of matter, which is an evil, but it brings together 

 in notes on life-history, structure, and especially on habitats and 

 date of occurrence, an immense number of facts, culled from 



