100 NOVJTATES ZOOLOGICAE XXIV. 1U17. 



Now, the names occidentalis and meridionalis were given by Staudinger in 

 his Catalog der Lepidopleren Europas, p. 8. No. 198. vars. b. and c. 1861. M. d. 

 occidentalis was given to Hiibner"s figures 869-7U [cinxi^i) and Henich Schaeffer's 

 fig. 133 {didyma var.) and figs. 324-7 (trivia var.). The latter, fi. 324-7, are 

 definitely stated by their author to have come from Mount Ararat, while his 

 No. 131 called by Staudinger under var. d. ^' dalmatina (araratica)" has no 

 locality given to it by the author ; from the name given to H rrich Schaeffer's 

 No. 131, viz. '' dalmatina {araratica)," it is evident that Staudiiiger inverted 

 the numbers by mistake, and that he really meant to call Herrich Schaeffer's 

 ff. 324-7 " var. dalmatina (araratica)" while intending to place that author's 

 f. 131 under occidentalis. 



As, however, Hiibner's ft'. 869-70 stand fii'st, we must accept these ff. as 

 the type of Staudinger's occidentalis, and as they evidently represent a Spanish 

 didyma, the name must stand for the Spanish form. Staudinger gives as the 

 habitat of his meridionalis Sicily and Turkey, and quotes no previous author. 

 As Sicily stands first, it is obvious that that is the type locality, and that 

 meridionalis will have to stand for the Sicilian form. 



This rules out Oberthiir's contention that both these names must be rejected, 

 and moreover fixes the localities of the types. It does not, however, finally 

 end our diflSculties, for there appear to be at least five if not six distinct local 

 races in Algeria which have all very well defined areas of distribution except 

 interposita Rothsch., which appears to be found in a number of more or less 

 isolated places in many Mauretanian districts surrounded by other forms. This 

 would pomt to its being an ABEREATION only, but it is constant in these 

 isolated localities, so it would appear that didyma is a species very rapidly affected 

 by local conditions, and that wherever the local factors which cause evolu- 

 tionary activity are of the kind aecessarj' to produce interposita, there that 

 form appears, and becomes fixed though it may be only in a small area com- 

 pletely surrounded by territorj" inhabited by otlier local races. Unfortunatclj' 

 I have no Spanish didyma for comparison, only Pyrenean examples, but Hiibner's 

 figure shows a very brilliant red insect with rather small spots and of a large 

 size. Moreover, it has pointed, extended forewings not rounded at the apices 

 as in Algerian specimens. I have sho^vn that this Spanish race must be called 

 occidentalis Stdgr., therefore the name mauretanica Oberth. can only by applied 

 to Mauretanian examples ; but here we are again met by a difficulty, for the 

 Moroccan specimens collected by Mr. Meade-Waldo are not, as stated by Mr. 

 Elwes, didyma deserticokt, but belong to my interposita, while the West Algerian 

 specimens generally belong to Mr. Oberthiir's mauretanica, and the extreme 

 East Algerian and West Tunisian specimens belong to another race which is 

 much smaller, and which I described as didyma nisseni (type Ain Draham). 



The specimens from the Northern Atlas Range in the Province of Oran 

 (Sebdou), the Kabylie (Djurjura), and the Aures Mountains all belong to my 

 interposita (type Batna), and which very often so closely approximate to didyma 

 deserticola Oberth. (type Biskra) that it is hard to distinguish them on the 

 upper side ; below, the heavier black markings of deserticola are at once apparent . 

 The form harterti from the Central Sahara is so distinct as to be at once dk- 

 tinguishable from deserticola above and below, and is unlike any other Jlaurc- 

 tanuin form. 



As stated before, in 1876 3L-. Oberthiir declared a series of PhUippeville 



