94 BRITISH BUTTERFLIES. 



adds (op. cit.) that, in both 1906 and 1907, he watched a kestrel feeding 

 on the same species ; it hovered just over the grass-stems and picked them 

 off one after the other while at rest. It is rare that this species overlaps 

 to any extent the first brood of A. thetis in Britain, for, although the latter 

 usually continues into July [see antea, vol. iii. (x.), p. 378] , yet it is 

 very unusual to see the two species together when A. coridon is just 

 commencing to appear ; on the other hand, it is a very common thing 

 to see the late A. coridon on the wing with the early A. thetis of the 

 second brood, in fact, for both to be waning together, and thus bearing 

 testimony to the laggard manner in which A. coridon supports its 

 single brood, e.g., Sabine notes both species flying together at 

 Folkestone, September 4th-7th, 1886. Adkin notes (Proc. Sth. Lond. 

 Ent. Soc, 1887, pp. 83-84) that, from August lst-28th, 1887,it was very 

 abundant on the downs near Eastbourne, some on the latter date were 

 quite fresh ; on August 28th, the first A. thetis (two $ s) were seen, on 

 September 16th both species were still out commonly, some of the A. 

 coridon yet quite fresh, and some of the A. thetis worn; the species 

 were, during this time, flying freely together and resting on the same 

 flowers. Similarly, in 1891 (op. cit., 1891, pp. 169-170), A. coridon 

 was abundant on August 1st at Eastbourne, and continued to be so 

 until September 3rd; A. thetis first appeared on August 22nd, and was 

 on the wing from then till September 3rd with A. coridon, when 

 observation ceased. The two species are not always abundant in the 

 same years, indeed, in certain abundant years for the one the other 

 may be almost absent, e.g., Stonestreet notes (Ent. Whig. Int., x., 

 p. 186) that, in 1861, A. coridon was very abundant, whilst Agriades 

 thetis and Melitaea cinxia failed almost entirely in the Dover district. 



Habitats. — As far back as 1798, Donovan noted this species as 

 being found " on the chalk-hills between Dartford and Rochester, 

 particularly on a long range of hillocks leading from Dartford to 

 the wood of Darenth," hence the butterfly has been called " the chalk- 

 hill blue." This is almost our own homeland, and thoughts of 

 Agriades coridon immediately raise in our mind the lovely stretch of 

 chalk downs running along both sides of the Medway above Rochester, 

 the similar stretches in the Isle of Wight behind Sandown and above 

 Freshwater Bay, the steep rocky chalk precipices looking out over the 

 Straits between Dover and St. Margaret's Bay, the breezy stretches 

 rolling back from Beachy Head, and many other of the choicest wild 

 spots still left in the southern counties of England. The species 

 haunts almost exactly the same kind of place as Agriades thetis, and 

 appears, like that species, to be confined to districts where Hippocrepis 

 roiimsa grows, but it reaches into Lincolnshire, Northampton, and Worces- 

 tershire, all north of the known habitats of A. thetis in Britain, whilst 

 there are records from the more northern counties of Lancashire, Cum- 

 berland, and Westmorland, some of which are now held to be not 

 al together free from suspicion by those who are most interested in the 

 fauna of these counties. There seem to be few suitable spots on the 

 North and South Downs that the species does not occupy, though its 

 absence from other apparently suitable 1 spots sometimes seems hard to 

 explain, and Oldaker notes it (in lift.) as common only in one particular 

 held on the Ran more slope, this being about a quarter of a mile distant 

 from the field in which A. thetis is abundant; it occurs similarly on 

 the limestoneand chalk- hills of Dorset, and the oolitic limestone of the 

 west, but is by no means absolutely confined to chalk and limestone 



