( Ixix ) 



disappeared. We meet with this development, which is illustrated on PI. LXIV. 

 by ligs. "J — lo, in Acheroittiiiiae and in Ambulichiae, also in the other subfamilies, 

 but here less often. The intermediate stages are numerous ; but these are 

 generally of little systematic importance, as it is scarcely possible to distinguish 

 diagnostically, for instance, between a long and a moderately long lobe. However, 

 intermediate stages in the development of the claw-segment are often wanting 

 between one species and its nearest ally, or between one genus and the next. 



The second line of development is represented by the two closely alliel 

 genera Kentrochrysalis and Sj///in(/ultus. The former possesses a complete 

 paronychium and a pulvillus ; the latter gejius has only a pnlvillus. Here 

 the paronychium has disappeared before the pulvillus. The intermediate stage 

 between the two genera is not known ; in this the paronychium would have one 

 lobe. Nor is the fourth stage without pulvillus, tlie one following Sphiinjulas, 

 as yet known. The fact of the pulvillus having been preserved in Sjikinguliis 

 and the paronychium lost is imjiortant. 8uch an exception from the general 

 rule demonstrates that an external cause determined which of the jwssible lines 

 of development tliat single species out of many had to follow. A similar 

 development occurs among the Ambtdicinae. 



Tlie scaling of the tars'is and tibia is sometimes a distinguishing character of 

 genera. As a rule the mid- and hindtibiae appear strongly compressed, owing to 

 the scaling being longer above and below than on the sides. The scaling between 

 and near the spurs is mostly long and tuft-like, and so is that ventrally at the 

 base of the first mid- and hindtarsal segments. In Pachi/gotiia the proximal 

 segments of tlie hindtarsns appear triangnlai'ly dilated, owing to a higli crest 

 of scales. The mid- and hindtarsi of Macroglog.stim and some other genera are 

 compressed, especially the first segment, which has become strongly asymmetrical, 

 its first inner row of spines being ventral, while the first outer row is almost 

 subdorsal. 



The singularly meagre success attained in the definition of genera of 

 Sphinyulae by the authors of the old school — meagre even from their point 

 of view — was mainly due to the wings seldom offering in the nenration such 

 obvious distinctions as are found in other families of Lepidoptera. The nenration 

 is indeed surprisingly constant in the main features, apart from some exceptions 

 like Cephonodes with a very short cell to the hindwing, and Daphnusa with 

 SC^ and R' of the hindwing on a long stalk. In consequence of this relative 

 constancy, the nenration of a Sphiugid can scarcely be confounded with that of 

 species of ether families. On the forewing (PI. LXV. f. 1) we find a five-branched 

 subcosta, S(' ; the first branch, SC, arises between middle and end of cell ; SO'' 

 and SC are on a long common stalk branching off before the ujiper angle of the 

 cell ; from this stalk SC'^ turns towards the costal margin not far from the tip 

 of >S(_'\ In very many species, or in many individuals, SCI- is not present at all, 

 it being generally either very weak or absent ; the vein is of no constancy 

 whatever, and consequently of no taxonomic value within the iamily. SC^ ends 

 in the distal margin just below the tip of the wing, and joins here soipetimes 



