ear
the root of the wing in the _male, without blue in the female_. Under side,
_pale grey-drab_, bluish near the base, marked with rows of _black spots_
in pale rings. _No red spots._

_Caterpillar_, green, orange stripe down back, and streaks of same colour
on each side.

The _butterfly_ is out in May and June, and is sometimes seen much later.
It is generally met with on limestone or chalky soils; and, from a long
list of localities I have looked over, it seems to be distributed over
England, Scotland, Wales, and Ireland.

* * * * *

{153}

THE MAZARINE BLUE. (_Polyommatus Acis._)

(Plate XIII. fig. 5, Male; 5 _a_, Female.)

_Colouring_:--Upper side, male, _deep purple, or mazarine blue_, with a
_border of black_ (fig. 5); female, _dark brown_ (fig. 5 _a_). Under sides
of both sexes similar, _pale greyish drab_, tinged at the base with
greenish blue, numerous _black spots in white rings_. No red spots.

Though this elegant butterfly was frequently met with some years ago, it
has lately become one of our rarest species, and I can give no locality
where it can be now found. It has been _reported_ as taken lately at
Ventnor, Isle of Wight, and somewhere in South Wales, also in other places,
but only singly.

Collectors, on visiting any new district, should net all the Blues they are
not _quite_ sure are common ones, and this may perchance turn up among them
sometimes.

The _caterpillar_ is said to feed on the flower heads of common Thrift
(_Armeria vulgaris_).

The _butterfly_ may be _looked for_ in July.

* * * * *

{154}

THE LARGE BLUE. (_Polyommatus Arion._)

(Plate XIV. fig. 1.)

This is the _largest_ of all our "Blues," and, next to the last, the
rarest, though still taken in some numbers every year.

_Colouring_:--Upper side, _dark blue_, granulated with black scales that
give it a dull aspect, having a black border, and a series of _large black
spots across the front wing_. Under side, greyish drab, suffused with
greenish blue near the body; towards centre, many black spots in indistinct
light-coloured rings, and a double border of the same. _No red spots._

The _caterpillar_ is _unknown_.

The _butterfly_ appears in July, frequenting rough, flowery
pasture-grounds, but is exceedingly local. A famous place for it is
Barnwell Wold, about a mile and a half from the village of Barnwell, near
Oundle, Northamptonshire, where the i