May 1S95.] 



PSYCHE. 



■2Z1 



sight, from the shape and size of the 

 wings, reminds one of a Micropteryx 

 or Eriocephala, while it also has a few 

 scales like those of these moths. 



But that the system of venation of 

 Spuler is morphologically the correct 

 one is fully and satisfactorily proved 

 by the ontogenetic development of the 

 veins. Fritz Miiller (Kosmos i, p. 390) 

 was the first to examine the incipient 

 venation of two semi-pupal motlis 

 {Castnia ardahis). He observed that 

 in the immature pupa the cross veins 

 were wanting, and that diflereiit longi- 

 tudinal veins, which afterwards more 

 or less completely disappeared, were 

 present, and hence he regarded the 

 pupal venation as the primitive one. 

 This view Spuler has adopted anil 

 extended, and it plainly enough, sup- 

 ported by the researches of Brauer and 

 Redtenbacber on the venation of the 

 nymph of Odonata, solves the problem 

 of the venation of insects in general, 

 and especially for Neuroptera, Trichop- 

 tera, Mecoptera (Panorpidae). Lepi- 

 doptera and Diptera. 



Spuler's method was to strip oft' the 

 loose skin of a caterpillar just beginning 

 to pupate, and examine the incipient 

 venation of the wings of the young 

 pupa on the living insect. He placed 

 the living pupa in water and then, 

 since the process of thickening and 

 resulting concealment of ihe veins of 

 the wing is retarded, _ the tracheal 

 branches become slightly enlarged, 

 filled w'ith air, and thus are more 

 easily seen. Hence small pupae from 

 which the larval skin has just been cast. 



and are transparent, are the fittest 

 objects for examination. 



The primitive and generalized con- 

 dition of the semipupal wing is shown 

 in Spuler's figure of Ccnira vimtla 

 (Fig. 2), to which we have addeti tlie 



numbering of all the veins. He shows 

 that ihe fundamental pupal venation of 

 Lepidoptera will also appl)' to Orthop- 

 tera (Blatta), Hemiptera, Trichoptera, 

 etc. He proves that the cross veins are 

 of quite secondary and suboi'dinate 

 importance. The results of Spuler's 

 investigations, extended through dif- 

 ferent groups from Tineina to Rho- 

 palocera, and illustrated by many 

 figures, are both interesting and con- 

 vincing. The comparison of the 

 venation of the fore wintj of the adult 



Fig- 3 



of GracHaria syringclla (Fig. 3 A) 

 compared with that of its semipupa 

 (Fig. 3 B), shows that the generalized 



