Distribution of Moths of the Sub-family Bistonincs. 71 



therefore, were evolved to the south of the main group, which, 

 whilst a creation of Eastern Asia, was still northern and 

 temperate in its preferences. 



Buzura arose in China and struck out soon after its devel- 

 opment in all possible directions, the line of least resistance as 

 regards climate being southward into India where, indeed, 

 the conditions were so propitious that it spread far and wide 

 in forms differing widely in wing-markings from the familiar 

 Buzura suppressaria. When it proceeded forth on its travels, 

 it was so clearly and well marked as to make it a worthy 

 bearer of the name benescripta bestowed on it by Prout. Nor 

 did it part with its wing pattern early, for it pressed onward 

 unchanged over the lowlands which then linked up India and 

 South Arabia from the Gulf of Cutch to the Kuria Muria 

 Islands, and into Africa. Naturally favouring subtropical 

 regions, it did not avail itself of the great highway open to it 

 down the Great African Plateau. On the contrary, after it 

 entered Africa, this event occurring almost certainly to the 

 north of Abyssinia, it kept forging ahead and ever to the west 

 until it was brought finally to a halt by the Atlantic Ocean. 

 In consequence, it has been side-tracked into all the areas 

 around the Gulf of Guinea where it has separated into the 

 closely allied species, Buztira abruptaria and B. analiplaga, 

 the disjunction proceeding from the difference between the 

 coast belt of forest and the drier and less densely wooded 

 hinterlands of Nigeria and Senegal. 



In later days, in India, the Buzura suppressaria which 

 went west in its migrations has shed its clear markings, and 

 truly deserves the appellation suppressaria for, except for the 

 powdering of darker scales, but few of the typical Amphid- 

 asyd markings are retained ; yet, before this pattern degenera- 

 ted, it had yielded the species Buzura varianaria. 



To return to the species of which the genus consisted when 

 it had but one exponent. 



Gradually from it there emerged a form which, not needing 

 the huge ' wireless ' system of the primitive Buzura antennae, 

 cast it aside and thus gave the subgenus Blepharoctenia. This, 

 too, must have been a later event, for when the insect migrated 

 it found exit from India on the west impossible. Eastward 

 and Southward, ground could still be gained and B. thibetaria, 

 which is as close to the old form as we can get, spread eastward 

 over the Chinese plains, in the end advancing into Formosa 

 which then cannot have been an island. There its insular 

 position has transmuted it into the species B. perclara. 



The mass journeying into the Indo-Chinese Peninsula, at 

 first seems to have been a broad one, streaming into India 

 through Assam between the mountains and the coast, leaving 

 by the way-side the form B. bengalaria. Finally it came to 



1918 Feb. 1. 



