136 Bibliograpliical Notice. 



]Mr. Dallas commences his volume with the definition of an Insect 

 (" our bill of fare will consist exclusively of Insects ; hut what is an 

 Insect?"); and then alludes to the main features which separate the 

 Insecta proper from the three allied divisions of JSLjriapocIa, Ara- 

 chnlda and Crustacea. In the second chapter he discusses the " Struc- 

 ture of Insects in general," pointing out the particular adaptation 

 (of one, common type) v/hlch characterizes each successive Order. 

 That portion which refers to the several modifications of the parts 

 of the mouth is particularly lucid. It is satisfactory also to see that 

 Mr. Dallas is alive to those higher deductions from his subject in 

 which the doctrine of Final Causes in Creation takes its rise, and 

 which some of our (^i/a*?-* philosophers' have of late thought it their 

 special mission to sneer at. " Few things," says he, " coidd furnish 

 the natural theologian with a better proof of design in nature than 

 the investigation of the course adopted in the modification of the 

 same parts, which v.e have just seen in the form of powerful biting 

 organs, to constitute the agents of a suctorial existence ; nor is our 

 admiration in any degree lessened by the consideration that many of 

 the creatures in which these phtenomena are to be witnessed are so 

 small as almost to elude the naked eye, — for, in the words of the 

 late Professor Forbes, ' wonders are not the less wonderful for being 

 packed into a small com.pass.' " 



Chapter III. treats (first) of the sexes, and (secondly) of the 

 transformations of Insects, — both of which are ably and clearly 

 handled. As a favourable specimen of Mr. Dallas's style, we may 

 quote the following, concerning the latter of these : — 



" We meet with few more remarkable phceuomena, in the history 

 of animal life, than this of the metamorphosis of insects. When we 

 think that the same animal is at one period of its existence a crawling, 

 worm-like creature, devouring with the greatest voracity large quan- 

 tities of coarse food, and then, after passing a longer or shorter period 

 in a state of comparative inaction, inert and apparently almost dead, 

 makes its appearance as a butterfly, one of the most elegant and 

 aerial of beings, passing its whole existence in sporting in the sun's 

 rays, and deriving its sole nourishment from the delicate fluids of 

 flowers, it is impossible to restrain our admiration ; and although 

 modern science may have stripped the phceuomenon of much of the 

 marvellous which invested it with a greater glow of wonder in former 

 ages, it must be confessed that it has at the same time opened up to 

 us a source of more rational admiration by teaching us, that, what- 

 ever may be the apjiarent discrepancies between them, the same ele- 

 ments, nay, even the same i^arts, are ivesent in the one as in the 

 other, and that by this means one and the same animal is fitted for 

 the performance of two totally distinct duties in the grand oeconomy 

 of nature" (p. 46). 



Immeasurably the best portion of the book, however, as it appears 

 to us, is the short chapter on " Classification and Nomenclature" 

 (Chap. IV.), which is alike sound and philosophical; though we 

 doubt whether the definition of a " species, " however true, will be 

 sufiicient to satisfy at any rate a certain section, happily not a very 



