INSECTS 1441 



closely we see that the summit of each oval is, as it 

 were, cut off by a line, and by comparing the basal 

 joints with the others, we see that this line is the real 

 division, that the summit of the oval really forms the 

 bottom of the succeeding joint, and that the con- 

 stricted part is no articulation at all. The first, or 

 basal joint (called the scapus) , and the second (called 

 the pedicella), differ in form from the rest, here but 

 slightly, but often considerably. The whole of the 

 remaining joints are together termed the clavola. 



There is a very extensive family of beetles known 

 as Lamellicornes, because the antennal joints are 

 singularly flattened and applied one over the other 

 like the leaves of a book (lamella, a leaf). 



But this structure is seen to still greater advan- 

 tage in the much larger cockchafer, so abundant in 

 May in some seasons. The insect widely expands 

 them, evidently to receive impressions from the at- 

 mosphere; when alarmed, they are closed and with- 

 drawn beneath the shield of the head, but on the first 

 essay toward escape, or any kind of forward move- 

 ment, the leaves are widely opened, and then, after 

 an instant's pause to test the perceptions on the sen- 

 sorium, away it travels. 



But much more curious and beautiful are the an- 

 tennae of many moths, which often resemble feathers, 

 particularly in the group Bombycina, of which the 

 silkworm is an example; and in the male sex, which 

 displays this structure more than the female. 



This is the antenna of a large and handsome and 

 not at all uncommon moth the oak egger (Lasio- 

 campa quercus). It consists of about seventy joints, 



