Introduction. 5 



nature. A nomenclature raised upon artificial systems, and 

 which has not for its basis the general harmony which connects 

 all the parts of creation, is as repulsive, as it is unprofitable ; for 

 it disconnects the student from nature, the sole object of his pur- 

 suit. Such nomenclatures are becoming unpopular, natural sys- 

 tems are taking their place. The progress of science is uncer- 

 tain and unsatisfactory, when it is attempted by any other means 

 than practical observations of the affinities of the parts of nature. 

 This is the true basis of all classification. Direct agreements be- 

 tween any two natural objects, form a true nucleus for natural 

 families, which we increase by the accession of other individuals 

 existing under the same conditions. The division of animated 

 nature into two great groupes, vertebral and in vertebral, affords 

 great facilities to the student in zoology. Thus, all animals hav- 

 ing backbones and skulls, are separated from all those without 

 them, and which are protected by shells, and other external 

 coverings. Here there is an apparent gap in the order of na- 

 ture. Although we can profitably avail ourselves of the advan- 

 tage this zoological division affords us in the study of nature, 

 yet it by no means authorizes us to say, that nature has here 

 made a jump from one scheme of structure to another, but 

 rather it becomes us modestly to suppose, that our own observa- 

 tion is at fault, and that this apparent gap will ere long be filled 

 up by the industry and genius of man. Liberal and active minds 

 rejoice most in the contemplation of difficulties of this character; 

 and certainly it is wiser, instead of being astounded at this spe- 

 cious transition, and proceeding to raise systems upon it, to take 

 comfort in it, as hiatus non deflendus. Each of these great 

 divisions contains innumerable objects, and by subdividing them, 

 and classing those together, which have the most marked affini- 

 ties for each other, we at length come to know all the individuals 

 in nature, by designations drawn from features, which not only 

 separate them from the rest, but which at the same time reflect 

 their true place in nature; as the prismatic rays do for the 

 beam into which they naturally blend themselves. In this man- 

 ner the Conchologist, the Entomologist, the Botanist, the Miner- 

 alogist, acquire without effort the knowledge of several hundreds 

 of thousands of objects in nature. We advise our readers, then, 

 not to be deterred by difficulties which are more apparent than 

 real; and not, on this account, to avert themselves from the great 



