Bibliographical Notices. 415 



for the microscopist ; the classes, orders, famihes, and genera of the 

 lower sections of both kingdoms are characterized ; their leading 

 peculiarities, both of structure and habits, are pointed out, and evea 

 a considerable number of species are described. 



It may be thought that a systematic treatment of this part of the 

 subject would have been preferable ; but for many reasons we are 

 inclined to think that the authors have exercised a sound discretion 

 in adhering to the Dictionary form throughout. Such a work as this 

 is obviously not to be regarded as presenting its readers with a com- 

 plete system of nature ; many departments of the system only require 

 to be touched upon, or to be treated in a very different way to others : 

 this may be done with great propriety in a Dictionary, whilst the 

 same mode of treatment in a systematic form would give rise to 

 irregularities and an apparent patchiness in the book, which could 

 not but have been distasteful to a critical eye. Moreover, the 

 alphabetical arrangement is of great advantage to those com- 

 mencing and carrying on a discursive study of the whole range of 

 natural history, such as is usually cultivated by the true microsco- 

 pist ; for they not unfrequently obtain an object and its name at the 

 same time, when by means of this Dictionary they may easily learn 

 something of the structure and properties of their acquisition. On 

 the other hand, by the arrangement which has been carefully followed 

 throughout by the authors, by which the groups included in each 

 superior group are briefly referred to under the latter and more fully 

 in their proper place in the alphabetical series, it is easy for any one 

 to work out any of the forms of animals and plants mentioned in the 

 volume, especially as this process is greatly assisted by a copious 

 series of cross-references ; and any one desirous of obtaining further 

 information upon any point has the means of so doing placed within 

 his reach by the excellent bibliographical references appended to each 

 article. These bibliographical memoranda are indeed of the highest 

 importance, and will render the ' Micrographic Dictionary' a valuable 

 handbook even for the advanced student of nature, to whom, more- 

 over, the having such a vast mass of scattered zoological and botanical 

 knowledge brought together within the compass of a single volume 

 cannot but be exceedingly convenient. 



The preceding remarks upon the scope and plan of this work 

 apply equally both to the first and second editions, and we have still 

 to indicate in what respects the latter differs from its predecessor. 

 And this second edition comes to us with a sort of melancholy feel- 

 ing, as the last work to which one of its distinguished authors set his 

 hand ; the press proofs of the last three sheets were only waiting for 

 his finishing touch, when the hand of death fell suddenly and prema- 

 turely upon Professor Ilenfrey, in the midst of his indefatigable 

 labours. The portion of this volume which we may consider as fall- 

 ing more particularly under the care of this amiable and lamented 

 botanist has required comparatively little alteration. In regard to 

 the general structure and classification of plants, little change hag 

 taken place within the last few years ; and accordingly the botanical 

 articles remain much as they were. Nevertheless we find abundant 



