Stark^s Elements of Natural History. 171 



iiera and species ; and that in the popular details much of the wonderful 

 related by travellers is softened down to the capability of sober belief, with- 

 out lessening the interest excited by the real wonders in the structure 

 and instincts of living beings. 



The second class of Vertebrated Animals, Birds, next follows ; and here 

 the scientific details are also preceded by an introduction explaining the ana- 

 tomical peculiarities of structure, the general forms and habits of this group 

 of animals, with explanations of the terras used in description, and a his- 

 torical summary of the chief methods of arrangement. " The arrangement 

 of Birds into orders (says Mr S.) has for its basis the conformation of 

 the bill and feet, which are adopted to their different modes of living and 

 food. Birds of Prey are characterized by a hooked bill, and feet armed with 

 strong and crooked nails ; Climbers are those, the structure of whose feet 

 is calculated for motion on an inclined or vertical surface ; and web-footed 

 birds are evidently adapted for swimming. Others again have the legs 

 very long and naked for wading ; and a large number, with the claws short 

 and feeble, live chiefly on insects. But though it be thus easy to separate 

 the more strongly marked groups into extended families, yet it has been 

 found extremely difficult to distribute them in subordinate groups, so as 

 to facilitate the knowledge of species in a class so widely extended. In 

 adopting the arrangement of Temminck, therefore, though his Orders are 

 more numerous than those proposed by Cuvier and Vieillot, yet the fa- 

 milies of the latter are in much greater number ; and in an elementary 

 work it has been judged proper to follow that system which involves the 

 least change of the established nomenclature as likely to be most generally 

 useful." The number of orders in this class, which it is not necessary to 

 enumerate here, is sixteen, and Mr Stark gives, besides the generic charac- 

 ters of the whole class, descriptions of all the European species, and the prin- 

 cipal foreign species. The notes on this portion are extremely interesting, and 

 convey much information not generally known- We copy one or two of 

 the general remarks. " The Class of Birds, though not so apparently use- 

 ful to man as the Mammalia, serve important purposes in the general eco- 

 - nomy of nature. Those whose food is chiefly insectivorous check the ex- 

 cessive reproduction of the insect races, and for this purpose migrate at cer- 

 tain seasons to places where their food abounds. The indiscriminate de- 

 struction of crows and sparrows in some districts has accordingly been found 

 to give rise to an infinitely more prejudicial multiplication of creatures still 

 more destructive. Some families of birds destroy field-mice, snakes, frogs, 

 and lizards; and others again are led by choice to feed on carrion, or dead 

 animal matter. Birds are, besides, extensive agents in the spread of vege- 

 tables and even animals. It is well ascertained that wild ducks in their 

 emigrations carry impregnated spawn into remote ponds, and thus stock 

 them with fish ; and many, by swallowing seeds .whole, and subsequently 

 expelling them, are tlie means of spreading vegetation over an extent of 

 surface which scarcely any other means could accomplish. A great por- 

 tion of the class and their eggs may be used as food, and the feathers of 

 many form an object of commerce." — " The flights of migratory birds 

 have been noticed from the earliest periods. — * The stork in the Heaven 

 knoweth her appointed times, and the turtle and the crane and the swal- 



