P E E F A C E. 



HAVING often been requested by students of Natural 

 History to prepare a synoptical table of the classifica- 

 tion of the Animal Kingdom, the present work is an 

 attempt to comply with this requisition, and to sup- 

 ply what the author believes to be a want among 

 zoological workers. Nothing more, of course, could 

 be attempted in the preparation of such a synopti- 

 cal table than an enumeration of the sub -kingdoms, 

 classes, orders, and sub-orders, with, in general, the 

 families, and the principal genera illustrative of these. 

 It has not been possible, however, without unduly ex- 

 tending the limits of the work, to mention in all cases 

 all the families, and this deficiency is especially notice- 

 able in the case of such great groups as the Insects, 

 the Fishes, and the Birds. It has also seemed advis- 

 able not to give definitions, even of the shortest sort, 

 of the subdivisions which are actually enumerated, 

 except in the case of the sub-kingdoms only. It is 

 hardly possible to make such definitions satisfactory 

 within the limits here available ; and the introduction 



