SPHINGIDAE. 143 



FAM. VIII. SPHINGIDAE. 1 



The perfect insects included in this group are characterized 

 by the absence of simple eyes on the vertex at the base of the 

 antenna?. The head is well developed, and well clothed with 

 hairs, that but rarely show a tendency to become tufted; the 

 antennas are prismatic, and more or less thickened towards 

 the tip, where they are recurved in the form of a hook, and 

 surmounted by a ciliated seta; they are doubly .ciliated in 

 the males, on the sides of the plates prolonged beneath from 

 the stalk, and nearly simple in the females: in some genera 

 the terminal seta is obsolete, but the stalk is distinctly pris- 

 matic, and the articles are ciliated or bear short pectinations 

 in the males. The eyes are usually large, hemispherical and 

 salient, and the palpi have the third article reduced to a mere 

 point, placed on the summit of the well developed second 

 article. The tongue is usually well developed, and nearly 

 equal to the length of the body; in some instances it is more 

 than twice longer than the body, and in others it is almost 

 obsolete. 



The thorax is always well developed and large, containing 

 powerful muscles, that are attached to elongated, narrow and 

 dense wings, the inner border of which is much shorter than 

 the exterior, in consequence of the obliquity of the hind 

 margin, and are attached to each other by a bristle and hook. 

 They are characterized by,the following peculiarities of struc- 

 ture. The basal portions of the marginal and costal nerv- 

 ures are thick and strong, and contiguous to each other and 

 the subcostal nervure; these and the subcosto-marginal nerv- 

 ules proceed towards the apex of the wing almost like a 

 bundle of rods, thus forming an external margin capable of 

 resisting rapid and strong vibrations upon the atmosphere. 

 In addition to the two marginal nervules, given off from 

 near the posterior-superior angle of the disk, the subcostal 

 divides into a subcosto-apical, post-apical and inferior nerv- 

 ules. At the origin of the subcosto-inferior, the discal-nerv- 



1 The following monograph of the Sphingidae is the production of Dr. 

 Brackenridge Clemens, of Easton, Pa., and was published in the Journal 

 of the Acad. Nat. Sci. Phila., July, 1859. By his kind permission it is 

 inserted here. Everything is retained except the admirable paper on 

 Classification which precedes it, and some minor details, besides a few 

 Brazilian species. J. G. M. 



