PROF. J. O. WESTWOOD ON THE IIRANIID^. 511 



Adopting the opinion of M. Boisduval, that the group before us will not enter into 

 any of our generally received families, and that it is " une de ces creations a part, qui 

 envoie a la fois un rameau vers plusieurs groupes, mais que Ton ne pent faire entrer 

 convenablement dans aucun " (Mon. Agarist. p. 7, extr. Eev. et Mag. de Zoologie), we 

 must now investigate the natural relationships of this most interesting group of insects, 

 which have been alternately regarded as butterflies and moths. 



Thus Linnaeus regarded the more typical species as butterflies, and Fabricius even 

 placed them at the head of the day-flying genera. Dalman, as we have already seen, 

 considered that F. orontes formed the transition between the Papilionida; and the other 

 Uraniidse. Latreille (Gen. Crust, et Ins. iv. p. 207) gave Urania and Hesperia as the 

 two terminal genera of the Diurna, and Castnia (into which he introduced P. orontes) as 

 the first genus of the Sphingides. The same arrangement was employed in the 9th 

 volume of the ' Encyclopedie methodique,' where Godart divided the genus Urania 

 into four groups : — A, Ripheus ; B, Sloaneus and Leilus ; C, Orontes and Patroclus ; 

 D, Lunus and Empedocles. In 1825 (Fam. Nat. du Regne An. p. 470), and in 1829 

 (Regne An. 2nd edit. iv. p. 387), Hesperia and Urania are still given by Latreille as 

 two genera of Hesperiidw, and Castnia, Coronis, and Agarista of Leach as forming the 

 first tribe {Hesperi-Sphinges) at the head of the Sphingidse. 



This arrangement continued unchanged by Latreille to the last, and was adopted by 

 his more immediate French followers. It had, however, in the meantime met with 

 opposition in Germany and Sweden, Hiibner in 1816, as we have already seen, having 

 placed the entire group amongst the Geometridse, while Dalman had removed them 

 from the Diurnal Lepidoptera to form his uncharacterized group Nyctalideae with P. 

 orontes as the connecting link between them and the butterfiies. M. Guenee, however, 

 did not hesitate in 1857 entirely to reject their relationship with the Diurna, showing 

 that with respect to the characters derived from the spring and socket at the base of the 

 wings, the form of the antennae and palpi, the structure and armature of the legs, and 

 the venation of the wings, together with the form of the larvae, so far as known at that 

 time, these insects had no real relation with the Diurnal Lepidoptera (Hist. Nat. Ins. 

 Lep. ix. p. 3), that they formed one entire group, and that they ought to be placed 

 among the Noctuma ; in fact, although by being placed by some writers at the head of 

 the Heterocera their supposed relationship with the Hesperiidte has been in a manner 

 kept up, the pointed tips of the antennae of some of the species, and the spines on the 

 hind legs favouring such a view, they exhibit no real relationship with the Hesperiidae. 

 In like manner a comparison of the structural details which I have given in the 

 accompanying plates, with those of the Castniidae and Hepialidee published in my re- 

 cent memoir on the former family in the ' Transactions of the Linnean Society,' will 

 clearly show that the relationship of Coronis with Castnia as indicated by Latreille, and 

 that of Urania with Castnia as suggested by Macleay in this Society's ' Transactions,' i. 



p. 188, must be completely ignored. 



4b2 



