chap. x.J THE PALiEARCTIC REGION. 187 



strengthen our view of their radical distinctness, by showing to 

 how considerable an extent the former is inhabited by peculiar, 

 and often very remarkable generic types. 



Insects : Lepidoptera. — The Diurnal Lepidoptera, or butterflies, 

 are not very abundant in species, their number being probably 

 somewhat over 500, and these belong to not more than fifty genera. 

 But no less than fifteen of these genera are wholly confined to 

 the region. Nine of the families are represented, as follows : — 



1. Danaidce; having only a single species in South Europe. 



2. Satyridce ; well represented, there being more than 100 species 

 in Europe, and three peculiar genera. 3. Nymphalidce ; rather 

 poorly represented, Europe having only about sixty species, but 

 there is one peculiar genus. 4. Libytheidm ; a very small family, 

 represented by a single species occurring in South Europe. 



5. Nemeobiidce ; a rather small family, also having only one 

 species in Europe, but which constitutes a peculiar genera. 



6. Lyccenidw ; an extensive family, fairly represented, having 

 about eighty European species ; there are two peculiar genera 

 in the Palasarctic region. 7. Pieridm ; rather poorly represented 

 with thirty-two European species ; two of the genera are, how- 

 ever, peculiar. 8. Papilionidce ; very poorly represented in 

 Europe with only twelve species, but there are many more in 

 Siberia and Japan. No less than five of the small number of 

 genera in this family are wholly confined to the region, a 

 fact of much importance, and which to a great extent redeems 

 the character of the Palaearctic region as regard this order of 

 insects. Their names are Mesapia, Hypermnestra, Doritis, 

 Sericinus, and Thais ; and besides these we have Parnassius — 

 the " Apollo " butterflies — highly characteristic, and only found 

 elsewhere in the mountains of the Nearctic region. 9. Hes- 

 peridcc ; poorly represented with about thirty European species, 

 and one peculiar genus. 



Four families of Sphingina occur in the Palsearctic region, 

 and there are several peculiar genera. 



In the Zygmnidm there are two exclusively European genera, 

 and the extensive genus Zygoma is itself mainly Palaearctic. 

 The small family Stygiidas has two out of its three genera 



