PREFACE. vii 



of habits is dependent on so many contingencies, as to require the careful 

 preservation of life under the best conditions. 



From such indispensable requisites for a Treatise on Natural History, 

 it is obvious that the taste and qualifications of the historians of each must 

 be diversified in their respective departments, that their opportunities 

 shall be favourable, and their labours protracted. 



The operations of Nature undisturbed, are those which demand our 

 confidence. The real organization and habits of the inferior tribes are 

 never displayed unless in a tranquil, vigorous, and healthy state. When 

 under constraint, placed in an unsuitable medium, or enfeebled by disease, 

 the finest specimens languish : they alter and contract, the relative position 

 of their parts is disturbed, their functions are impaired : the organs most 

 conspicuous or most important during life, often disappear entirely, or they 

 are changed by death, beyond the hope of recognition. Thence can we 

 do otherwise than reprehend and distrust the cruel operations and assumed 

 results whereon too many modern anatomists have founded theories, from 

 living animals — rather from animals in the agonies of death ! 



It is vain for one individual to claim the concentration of so many 

 qualities as are necessary for the illustration of the natural history of even 

 a single subject of the animal world ; whence, conscious of the superiority 

 of my more distinguished fellows in the science, I confine myself to a 

 narrow sphere. 



My principal aim has been to render the external aspect and the 

 habits of certain species of the lower orders more familiar to others, and 

 especially to those who may not have had equal opportunities of personal 

 observation. 



In doing so, I have endeavoured to select the most vigorous living 

 specimens of their kind ; and along with a general description, to present 

 their resemblance from delineations by the most skilful artists. Nothing 

 is described, nor scarcely alluded to, unless represented ; for it is irksome 

 to read of what cannot be otherwise understood. 



By suitable precautions, I have been enabled to preserve individual 

 subjects, one, two, nay, even ten or twenty years, and, by this long ac- 

 quaintance, to gain some information of their character. 



