214 JOHN B. SMITH. 



wing form. Under the term Paonias I unite three species again 

 agreeing in type of genital structure in having a frontal crest be- 

 tween the antennte, a rather narrow and indistinct, somewhat dis- 

 colored thoracic crest, more conic aljdomen, and in having the ocellus 

 of secondaries without a black centre, and not connected with the 

 anal angle ; the apex of secondaries is lobed and the costal margin 

 is sinuate. In this genus, too, there is some diversity in the outer 

 margin. At the end of the series I place Cressonia, which is isolated 

 from its allies in antennal structure — the males have the antennse 

 doubly bi-pectinated, each joint bearing two branches on each side. 

 Clemens has observed this structure without deeming it of generic 

 importance. The palpi, too, are unusually long, and are divaricate — 

 all of them features which isolate the genus from all other American 

 Sphinges. 



The habits of the species are nocturnal. Having no tongue they 

 are incapal)le of feeding ; the wings are not built for sustained or 

 rapid flight, the thoracic muscles being too little developed. They 

 fly to light, however, and in that way many are taken. The larvie, 

 withal, are truly Sphingiform, and have the anal liorn ; they are 

 granulated, and have the head triangular. Other particulars in re- 

 gard to the larva3 may be gathered from the Introduction. 



The pupie are all subterranean and make no cocoon of any kind. 



In tabular form the genera and species may be placed as follows : 



1. Antemise of male doubly bi-pectiuated, palpi divaricate at tip 5. 



Autenuie of male ciliate or .singly pectinated, palpi closely applied to front 2. 



2. Costal margin of secondaries sinuate, the apex produced or lobed 4. 



3. Size large, thorax immaculate, anterior tibia with a long, strong curved claw, 



secondaries not ocellate Triptogoii luodeMta. 



Smaller, the thorax with the dorsum between the patagise dark brown, second- 

 aries ocellate Smeriiitlnis. 



AntennsB of male pectinated; ocellus of secondaries with two blue pupils; 



fore tibiae not armed S. geniiiiatiis. 



Antennte of male ciliated ; ocellus of secondaries single ; fore tibite with a 

 spine at tip. 



T. p. line not lunulate S. oplitlialiiiictis. 



T. p. line lunulate S. eerysii, 



4. Thorax with a narrow, slightly discolored crest ; head crested between the 



antenna; Paonias. 



Outer margin regularly scalloped P. e.xOiPCaf us. 



Outer margin not scalloped, simply slightly produced on veins 1, .3, 7 and 8. 

 Ground color deep chocolate brown with lilac powderings; maculation dis- 

 tinct P. inyops. 



Ground color pale yellowish brown, the maculation indistinct.. P. astyliis. 



5. Secondaries not ocellate Cressonia jug;lamlis. 



