NATURAL HISTORY. 



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Class VIII. ARACHWDA. (Gr. 'Apd^vfj^, a Spider.) 

 Order PULMONARIA* (Lat. Pulmo, the Lungs.) 



Family. . . Araneldrc. Lat. Ara?iea, a Spider.) 



MYGALE. (Gr. Mv)-aArj t the Shrew-mouse.) 



Avicularia (Lat. Aviculus, a fo'Mfe Bird], the Bird Spider. 



The Class ARACHNIDA, or the Spiders, are by many supposed 

 to be insects. Such, however, is not the case. The Arachnida 

 possess eight legs, while the true Insects only have six ; they 

 undergo no transformations, they possess no wings or antennee 

 (the place of the latter organs being supplied either by two 

 jointed claws, as in the Scorpions, or by two fangs, as in the 

 Spiders) ; and their eyes are simple instead of compound. 



Could people divest themselves of the horror felt at the sight 

 of these creatures, especially of the larger sort, they would be 

 well repaid by the interesting instinct displayed by all the 

 Spiders, who do not differ from each other more in form than in 



* So called, because the animals belonging to this class breathe by means of air- 

 sacs, called by Latreille, Pneumobranchiae, or lung-gills. The Trachearia, on the 

 contrary, breathe by means of tracheae, or air-tubes branching through the whole 

 system, like the insects. 



