REVIEWS OF NEW PUBLICATIONS. 389 



consequently placed the suctQrial Lice (Pediculidce) in the order Hemiptera, and 

 the mandibulated Lice (Nirmidce) and Spring-tailed insects (Lepismidce) in 

 Neuroptera! Mr. Westwood justly objects to this unwarrantable innovation. 

 He is of opinion that Dr. Burmeister "has been led to adopt this arrangement 

 by giving too slight a weight to the organs of flight ;" and in the proofs cited in 

 favour of his system, Mr. Westwood '• can see but exceptions to a general rule, 

 for which allowances ought to be made, and, consequently, as not warranting the 

 introduction of entire groups of apterous animals into the class." — p. 6. 



We now arrive at Mr. Westwood's classification. He considers that insects 

 may be defined to be 



" Annulose animals breathing by trachea? ; having the head distinct ; and provided in the adult 

 state with six articulated legs ; subject also to a series of moultings, previous to attaining perfec- 

 tion, whereby wings are ordinarily developed." — p. 1. 



He thus excludes the entire Arnetabola, Auct. (Myriapoda, Thysanura, and 

 Parasita of Latr., &c), which he considers, with Mac Leay, as constituting a 

 distinct class, " having no metamorphosis, in the usual sense of the word, or only 

 that kind of it the tendency of which is confined to an increase in the number of 

 feet." In thus adopting Mac Leay's classification, he wishes to be understood as 

 having done so 



"Because it leaves the true winged metamorphotic insects as distinct from the other groups, 

 and without expressing any opinion upon the quinarian views of Mr. Mac Lkay, or upon the 

 introduction of the Vermes amongst the Arnetabola. n — p. 4. 



After having determined (and we think justly) the limits of the class Annulosa, 

 he proceeds to the structure of insects. The chapter devoted to this subject 

 contains much interesting and well-condensed matter. We have not space to 

 discuss the questions touched upon in his remarks on the " Distribution of Insects 

 into Orders," but consider them well worthy of attention, although by no means 

 convinced of their correctness in every respect. Then follows a list of works 

 devoted to Coleoptera, and remarks on Ijhat order. We can only give a very 

 brief summary of this part of the subject. Linnaeus divided Coleopterous insects 

 into the three following sections : — Antennis clavatis extrorsum incrassatis ; 

 Antennis filiformibus ; and Antennis sctaceis. Olivier distinguishes the pri- 

 mary sections of the order by the variations in the joints of the tarsi. The tarsal 

 system was rejected by Mac Leay, who proposed divisions founded upon the 

 peculiarities of the larvae. The application of this theory throughout the entire 

 order, Mr. Westwood considers impossible. In this opinion he is supported by 

 Kirby, who in the Fauna Boreali Americana considers that Mr. Mac Leay's 

 system cannot be adopted through the " mazy labyrinth " of Nature, and regards 

 it as impossible " either to conceive or delineate it so as to maintain all its con- 

 nexions undisturbed and unbroken. We must do it in a series, which can only 



YOL. III. — NO. XXII. 3 F 



