Some caterpillars, from eggs laid in May or June, become full-grown in four or five weeks, and appear as butterflies in August, but others do not complete their growth until the following spring. Just exactly what happens in the case of eggs from autumn females does not seem to be very definitely ascertained. It has, however, been stated that caterpillars hatching from eggs laid in August, attain the size of the slow-growing contingent from May eggs, and then hibernate. Probably, therefore, it is these that produce the July butterflies, and if so, the succession of emergences may be something in this way: May and June butterflies from May and June eggs (twelve months' cycle), July butterflies from August eggs (eleven months cycle), August and September butterflies (partial second brood) from May and June eggs (four months' cycle). This interesting little butterfly is to be seen almost everywhere, but it is perhaps most frequently to be found in grassy places in lanes, on heaths and downs, railway banks, in rough meadows, etc. It occurs on mountains even up to an elevation of 2000 feet. When flying in company with the blues and coppers, all frolicking together over some patch of long grass, the colour combination has an exceedingly pleasing effect. They rest by day, and sleep at night on grass or rushes. A common species throughout England and Wales, Ireland and Scotland, as far north as Nairn, also in the Outer Hebrides. Abroad its distribution extends over Europe to South-West Siberia, Central and North-East Asia, Asia Minor, and North Africa. * * * * * We now arrive at the Hairstreaks, Coppers, and Blues. These belong to the Lycænidæ, a very large family of butterflies which is represented in all parts of the globe. There are eighteen species in Britain, but at least one of these is extinct and another is supposed to be so; two are very rare, and the chances of meeting with either are probably about equal. The Brown Hairstreak (_Zephyrus betulæ_).