11 



acquaintance. Here also a reference is needed to the species with 

 similar cinxiid tendencies which have already been mentioned in 

 connection with varia in Asia. 



And this brings us to the great puzzle of the origin of the ciu.ria- 

 group. The absence of high mountain or really arctic species of 

 this group, and the fact that it reaches further south both in Asia 

 and Africa than any other group of the genus point distinctly to its 

 more modern origin, a theory supported by the instability of the 

 two dominant species phabe and diihjina : but down in Colorado, 

 almost at the southern limit of the genus in North America, we 

 find the tiny species perse which apparently differs from cin.via in 

 nothing but its very minute size, and whose claims to specific rank 

 at all would seem difficult to maintain. Now, how did it get there? 

 Its existence seems almost to prove either that the actual cin.cia- 

 form had been evolved at a common centre, and that the species 

 was once very widely distributed in the extreme north, where it is 

 no longer found, or that a precisely similar form has been evolved 

 in the two hemispheres on a difterent line of descent. The former 

 hypothesis points to an antiquity for the species against which 

 everything militates, and the latter presupposes a persistence in this 

 species and a liability to extinction in all its neighbours which seems 

 quite incredible. This latter difficulty, however, occurs in a different 

 form even under the former hypothesis, for there is nothing what- 

 ever further north in America, so far as is known at present, to 

 make any connection between the cin.ria of the eastern and the perse 

 of the western hemisphere. One help towards bridging over this 

 difficulty is afforded by our experience of this insect in liritain, for 

 we know that ein.via is liable to become extinct in the most un- 

 accountable way. I do not believe that the attacks of collectors, 

 except when deliberate destruction by professionals has been prac- 

 tised (a very rare, though not an unknown occurrence), or in the 

 neighbourhood of large towns, has ever had any appreciable effect on 

 the extinction of a species, and in the case of ciiuia we know that 

 it disappeared from some of its recorded localities while the number 

 of British collectors must have been well under a hundred all told, and 

 the handiest way of getting from one place to another was the stage 

 coach. Its food-plant, again, plantain, is only too common and 

 wide-spread, its favourite haunts, such as landslips, deserted quarries, 

 and rough steep hill-sides are such as are never disturbed by the 

 agriculturist, it has few parasitic enemies (indeed, in the whole of my 

 experience I have never bred a single parasite from any Melitseid in 

 any stage),''' yet cinxia is probably quite extinct on the mainland of 



* Mr. L. W. Newman and Mr. H. Eowland-Brown have given it as their 

 experience that M. aurinia is extremely liable lo parasitism. I have only bred 

 this species in the jjrovincialis form, and bred no parasites, but the opposite ex- 

 perience here quoted shows that too much stress nmst not be laid on this argu- 

 ment. It is, however, difficult to believe that the attacks of parasites have 

 operated largely, still less extensively, as the cause of extinction. 



