STUDY OF VARIATION IN THE RACES OF ZYGAENA FILIPENDULAE, L. 125 



tracted eold weather impedes the growth of the larvre till late in the 

 season. The second emergence always consists, on the whole, of much 

 smaller individuals than the first. In my typical series from 

 Bolognola most males of the first reach 33mm. in expanse and a few 

 females reach 38, but the usual size is 35 to 37 in this sex and as many 

 as 18% of tlie males only measure 28mm. and 15% of the females 

 measure 30mm. ; they correspond also by their weakly build and pale 

 colouring to race paulula of subspecies lilipendidae. The second 

 emergence entirely consists of individuals of this size and aspect and 

 some males shrink to 26mm. and females to 29. It is noteworthy 

 that all the small individuals belong to the ochsenheimerl six-spotted 

 and narrow- margined form. At Bolognola 60% of the males and 

 nearly all the females have six spots, as shown by the statistical 

 table. It will also be seen by it that more than half the specimens 

 have a broader marginal band than inicrochsenheimeri, but, at Bolognola, 

 only quite exceptionally as broad as in medicaginis, Hb. Instead, on 

 the northern slope of Monte Morello, near Florence, at Fontebuona di 

 Vaglia, where Lepidoptera often have a high-mountain look, although 

 the altitude is only 400m., a race similar in size to ifwntivaga, but 

 distinctly darker, has been found. Here 20% of the males, and even a 

 few females have the hindwings darkened as in medicaginis and the 

 six-spotted form is reduced to 30% of the males and 60% of the females. 

 This is evidently due to the fact that we are within the limits of the 

 zone of high melanism of northern Tuscany. I think the designation 

 which suits this race is that of : 



Bace montivaga trans, ad medicaginis, mihi. 



Race etrusca, mihi. Duponchel states that the race from Nice he 

 calls medicaginis is also found in Tuscany. Oberthiir in his paragraph 

 on stoechadis and medicaginis says the same thing, but in this case he 

 does not distinguish these two races definitely. I think I now possess 

 a sufficient number of series from various localities in this region 

 to show there exist several distinct races, ranging from the one of the 

 plains, which is the reddest, to the very dark mountain aterri'ma, 

 through montivaga first and then through two grades more or less 

 identical to medicaginis, Hb., and stoechadis, Brk., of Piedmont. The 

 one of the plains is certainly parallel to duponcheli and to pyrenes of 

 France : it is a first step from ochsenheimerl towards darker races, just 

 like these two are a first step from major, Esp., to the same. Both 

 Querci and I, however, have been struck by its peculiar brilliancy, 

 which distinguishes it from any other race and calls for a distinctive 

 name. I propose that of etrusca, taking as " typical " my series from 

 the Pian di Mugnone, near Florence, collected in the locality so 

 charmingly described by Oberthiir in his Etudes, iv., p. 597 (m. 119- 

 274). The dark pattern is remarkably greener than is usual in this 

 species and the red is of a very clear and bright carmine. These tints 

 are evidently produced by the dryness and blazing heat of that 

 locality. In size it is distinctly large, like ochsenheimeri. The 

 five-spotted form, instead of being only a great rarity found in the 

 male sex, as in the latter, is found in about 60% of the males and 20% 

 of the females. This distinctly places it outside the group of six- 

 ~ spotted races. It will be seen in the statistical table at the end of this 

 paper that also the extent of dark markings on hindwing separates it 

 completely from ochsenheimerl; only 20% of the males and 5% of 

 the females resemble respectively its sexes, and even these individuals 



