172 [November 



tion of the wing is less thickly covered with scales, acquiring a paler 

 tinge than the basal portion. Posterior wings black, with a broad, cen- 

 tral, bright fulvous fascia, which contracts, triangularly, towards inter- 

 nal margin, before anal angle becoming somewhat linear and sinuate. 

 Beneath, the anterior wings at base are largely covered with bright 

 fulvous squammation; the central fascia on posterior wings is whitish. 

 Legs and under thoracic and abdominal regions, black. Exp. % 1.60 

 inch. Length of body .80 inch. 



The color and peculiar Sesia-like sericeous squammation of this 

 pretty species, are very suggestive of the hymenopterous genus Bora- 

 bus, notwithstanding the opacity of the wings. 



SESIA, Fab. emend, nob. 

 The generic term Sesia Fab. is used in a comprehensive and vague 

 sense at first by its discoverer, as an improvement upon Linnaeus' genus 

 Sjihiiix. In the Entomologica Systematica, p. 379, 1793, it is thus 

 defined: "/'a//)?! duo reflexi. L/j^^yua exserta, truncata. Antennse cj- 

 lindricae." Fabricius there includes under it first, certain species ot 

 Sphingidae which are comprised in the present Tribe Macror/Jo^slni ; 

 then the species of the Family JEgeriidoe (Sesiidae). Through the 

 observations of different Entomologists the term has at length been re- 

 stricted by Mr. Walker, in 1856, to the species with more or less vitre- 

 ous wings; that Entomologist using it in a synonymical sense to the 

 genus Cephonodes Hiibner, a genus of which Scsia llylas Fab. is the 

 type, and to which latter species, from autoptical examination, we are 

 satisfied it may with propriety be confined. In studying the Ameri- 

 can species grouped under *SV.s('a by Mr. Walker, we have become sat- 

 isfied that distinct genera have to be eliminated, and that the Eu- 

 ropean 8. fiicifurmix and S. homhyliformu, and the American S. 

 difiinis, off"er distinctive features from S. tht/she Fab. and allies, and that 

 to the former the generic term proposed by Fabricius should be restricted. 

 As thus understood, the genus IS'sia off"ers the following structural cha- 

 racters : The head is globose, free from the thorax; the palpi, which 

 are loosely haired, extend as far, but not beyond the steep clypeus. 

 The antennne are somewhat suddenly swelled towards their outward 

 extremity, and are much constricted at base. The prothoracic parts 

 are square in front, but moderately advanced before the insertion of 

 the primaries. The wings are small; anterior pair slightly depressed 

 at the apices, rounded along external margin, which is not very oblicjue. 

 The abdomen is wider than the thorax, stout and plump, ending rather 

 squarely, terminal segments not sloping down to the apex. The plump 



