L E I L U S Surinamensis. 



Surinam Emerald Butterfly, 



Family, Papilionidae. Sub-fam Papilionae. Genus, Lulus. Sw. 

 ( Fissirostral or Hesperian type) Sub-genus. Leilus proper. Sw. 



Synopsis of the Sub-genera. 

 I. Typical. Antennae filiform, thickened in the 



middle ; posterior wings with long pointed tails. Leilus. 

 ii. Sub-Typical. Antennae as in the last, but 

 arcuated near the tip. Tails of the posterior 

 wings short and obtuse. Orontes. 



jii. Aberrant. Antennae clavate ; front very 



hairy; tails none. Ripheus. 



Antennae clavate; wings hyaline; tails very long. Leptocircus. 



Specific Character. 



Wings black, varied with lines and bands of emerald-blue green : 

 posterior tailed ; the green spots round the margin running 

 into each other ; tails nearly ivhite. 



Papilio Leilus. Linn. Sys. Nat. 2. 750. Fab. Ent. Sys. 3. p 21. 

 Merian. Surin. pi. 29. 



Urania Leilus. Fab. Syst. Gloss. 



The Butterflys composing this remarkable genus are per- 

 haps the most splendid insects in creation. No art can 

 effectually represent the changeable and resplendent green 

 which relieves the velvet black of the wings, and which 

 varies with every change of light. The typical species are 

 found in Tropical America, where they ily with amazing 

 rapidity, and perform, like their prototypes the Swallows, 

 annual migrations. When at rest, the anterior wings are 

 flat or horizontal, but only slightly spread. The present 

 species appears confined to Surinam. 



Modern systematists have been peculiarly unfortunate in 

 the location and construction of this group; while the name 

 of Urania, bestowed upon it by Fabricius, has long been 

 appropriated to a genus of plants. Linnaeus, more correctly, 

 placed it with the genuine Pap i Ho ties ; a station which is 

 confirmed by the details of its structure : the anterior feet, 

 like those of Leptocircus, figured at pi. 106, being provided 

 with that short spiney process, which is a peculiar distinc- 

 tion of this sub-family. The analogies which result from 

 this location of Leilus are beautiful, and almost intermina- 

 ble. It is the representation of the Noctu'uhv and of the 

 JJesperidce in its own circle ; and of the fissirostral tribe 

 of birds ; all these being modifications of the natatorial 

 type of the vertebrata, 



y * 125 



