Professor Kaughton's Geology. 205 



but more importantly in the loss of old and the appearance of 

 new or unallied genera, so was the interval of time, shorter or 

 longer, that elapsed between the close of the lower and the 

 commencement of the upper formation • and so it often hap- 

 pens that strata a few yards in thickness, or, more notably still, 

 the absence of these strata, may serve to indicate a period of time 

 as great as the vast accumulation of the whole Silurian series." 



Professor Haughton is decidedly reckless iu the assertion 

 that whenever a creature deviates from the original type, the 

 result is a ' ' monstrosity," and an imperfection, and " not an 

 advantage." If Mr. Haughton selected . any kind of dog as 

 his original type, how could he demonstrate anything of the 

 kind ? He might show that particular breeds of dogs were 

 only capable of preservation under conditions of considerable 

 care and attention ; but it would not be true that spaniels, or 

 terriers, or hounds ought to be regarded as ' c monstrosities," 

 exhibiting " imperfections " and disadvantages jnst so far as 

 they differed from his original type. The pigeon fancier might 

 point to hardy and delicate varieties ; but could he not find 

 two or more varieties, differing considerably from each other, 

 and differing from the supposed primitive type, and yet 

 healthy and strong ? We do not believe that all departures 

 from particular types involve imperfection. That some devia- 

 tions are altogether mischievous we do not deny, and others 

 serve a particular purpose at a special expense of injury in 

 another direction. Our gardeners have however supplied us 

 with abundance of healthy varieties of plants, and our breeders 

 have assuredly produced healthy varieties of stock. 



We are sorry that we cannot speak more favourably of 

 Mr. Haughton's Manual of Geology. In many matters of 

 detail his acquaintance with specialities may show to advantage ; 

 but on the whole the book is a failure, the more unfortunate 

 from the position and reputation of its author. 



