ixx INTRODUCTION. 



above Compton and Freshwater Bays, which are open 

 to rough winds and within reach of the sea-spray, are 

 tlie habitats of some species. Several of the DelphacidaD 

 may be taken on the high Beacons of Derbyshire and 

 Worcestershire, and the Mountains of Scotland. 

 Finally, the sandy sea- shores of Komney and other 

 places, yield sorts which find their sustenance at the 

 roots of Aremiria and stunted maritime plants. 



As an anomalous habitat of the " dry Cicada," Mr. 

 Olliff's discovery of the habits of Tettix australis, Walk., 

 may be here cited. This species he describes as 

 floating on the surface of the Kiver Nepean, in New 

 South Wales. He remarks that the insect does not 

 confine itself only to the surface of pools, but that it 

 dives several inches below the water, and there clings 

 to the stems of water-jjlants. (See Proc. Ent. Soc. 

 Lond. for Feb., 1886.) 



It cannot be doubted that the colours of many Tetti- 

 gidae are protective. The green elytra of Tettigonia vlridis 

 closely resemble the bark of the green rushes amongst 

 which it lives. The sombre browns of many of the 

 Deltocephali accord well with the hues of the plants on 

 which they feed, and the grey shades of Idiocerus, in a 

 general way, render these insects inconspicuous on 

 the silver-like tints of the aspen and willow. The 

 question of the meaning of colour has recently been 

 so well discussed by Mr. Wallace, Mr. Poulton, and 

 Mr. Merrilield, that little can be here advanced as 

 new. If we look at colour merely as a mode of con- 

 cealment we find that a mere tint, however close it 

 may be to a particular surrounding, is not so efficacious 

 as a variety in marking, provided that the pervading 

 shades harmonise in tone. Amongst birds, the beautiful 

 barring of the nightjar {Cap-imulgus), the variegated 

 browns of the wryneck {Yunx), the ochreous and umber- 

 coloured blotches of the partridge, are all singularly 

 deceptive to tlie eye wherever the animals choose their 

 nests and make their haunts. 



Amongst Lepidoptera the imagoes of the buff-tip 



