The Origin of tha Markings of Caterpillars. 259 



We certainly do not yet know whether CEnotherce 

 possesses a horn in its earliest stages, although in 

 all probability it does so ; in any case the ancestor 

 of CEnothera had a horn, since the closely allied 

 P. Gaurce now possesses one. 



We thus see that also in the genus Pterogon 

 the marking of the caterpillars commences with a 

 longitudinal line formed from the subdorsal ; an 

 infra-spiracular or also a supra-spiracular line 

 (Gorgoniades) being added. A latticed marking is 

 developed from the linear marking by the breaking 

 up of the latter into spots or small patches, 

 which finally (in CEnotherce] become completely 

 independent, their connection with the linear mark- 

 ing being no longer directly perceptible. 



THE GENUS SPHINX, LINN. 



Of this genus (in the narrow sense employed 

 by Gray) I have only been able, in spite of all 

 trouble, to obtain fertile eggs of one species. 

 The females cannot be induced to lay in confine- 

 ment, and eggs can only be obtained by chance. 



I long searched in vain the literature of this 

 subject for some account of the young stages of 

 these caterpillars, and at length found, in a note to 

 Rosel's work, an observation of Kleemann's on the 

 young forms of Sphinx Ligustri, which, although 

 far from complete, throws light on certain points. 



From a female of S. LigustriYAzvK&xm obtained 

 400 fertile eggs. The caterpillars on emerging 



s 2 



