Zoology. — "77<(? value of generic and specific characters, tested 

 />// the 10 imj mar kings of Sphing ides' \ \^y Prof. .1. F. van Bemmelen. 



(Communicated in the meeting of October 26, 1918). 



Supposing the rules for the colour-pattern of Ihe wings, which 

 I deduced from former investigations l\y others as well as by 

 myself — to be valid, they onght to prove fit as guides in the 

 choice of a point of issue, when entering on the investigation of 

 a new group, that is to say when searching for a form which 

 shows the general pattern in its most original, least altered condition. 



Judging by those rules, I believe that among Sphingides, as far 

 as I am acquainted with them, Smerinthus popidi is a very original 

 form, in spite of the covering of red hairs, spread over the upper 

 side of the rootfield of the hind-wings, there hiding the primitive 

 pattern . 



The arguments for this opinion are the far-going similarity of fore- 

 and hind-wing, both on the upper and the underside, and the pre- 

 sence of a pattern, which over the entire wing-surface is built after 

 the same simple motive, viz. regular alternation of darker and lighter 

 transversal lines and bands, each composed of spots. In both the 

 dark and the light bands the spots show a strong tendency to the 

 semilunar shape (the convex side turned ontward), but here and 

 there they clearly approach the biconcave (hourglass) form. As to 

 the shades occurring as well in the dark as in the light bands of 

 spots, I pass them over for the present. 



On the upper side of the fore-wing two of the darker lines run 

 on both sides of the light discoïdal spot, and at a certain distance 

 from it, thus separating a darker median field from two lighter 

 transversal bands, which in their turn are again bordered by a 

 similar ribbonlike series of dark spots. Across this dark central area, 

 at the outside of the light discoïdal mark, another dark bar may 

 be distinguished, and in the distal part of the area, between the 

 last mentioned bar and the outer borderline, there also occurs a 

 series of spots, which however are far fainter. 



Moreover the anterior edge of the wing, on the inner side of the 

 discoïdal spot, shows a lighter hue than the rest of the central area, 

 which increases in darkness toward the posterior margin. In this 



