SKULKERS IN DRY FOOD MATERIALS 435 



it obtains a footing out of doors, as in a quarry at Slateford, 

 where Mr W. Evans discovered a colony in 1907, but such 

 colonies are always associated with material cast out of houses, 

 and seldom survive for long. Secondly, the distinct preference 

 shown by the House Cricket in Britain for artificial warmth 

 hints that originally it belonged to a tropical climate. 



An early Scottish reference to this insect is Sibbald's re- 

 cord (1684) of Grillus Focarius the Cricket on the Hearth. 

 Of recent years it has been carried to America in shipping 

 and has become firmly established, being especially common 

 in Canada. 



COCKROACHES 



The belief is almost universally held that the Common 

 Cockroach (Blatta orientalis] (Fig. 69, 4, p. 437), came to 

 Europe and to Britain in comparatively recent times from 

 tropical Asia. At the present day in Scotland it is common 

 where warmth and abundance of food offer it congenial con- 

 ditions, in kitchens, bake-houses, and, as Mr William Evans 

 has recorded, even in the warm underground workings of 

 coal-pits, as at Bo'ness and Dalkeith. But this general dis- 

 tribution is a recent development, for the Cockroach when 

 first referred to as a British resident, in 1634 by Moufet, 

 lived in wine-cellars and flour mills and was probably con- 

 fined to London and perhaps a few other great ports. Fifty 

 years later Sibbald recorded it, as ''Blatta, the Moth Fly, "from 

 Scotland. Its mode of arrival is tolerably certain, for Moufet 

 tells how, even in the sixteenth century, Sir Francis Drake, 

 on capturing a ship, Philip, laden with spices, found a vast 

 multitude of winged Cockroaches on board ; but whether 

 this was the Common or American species cannot easily be 

 decided. As befits an ocean voyager the Cockroach first 

 populated the seaports. Thence its spread countrywards 

 seems to have been a slow one, for it was not till about i 790 

 that Gilbert White found it in his own house at Selborne, 

 50 miles from London. In America the distribution of the 

 " Black Beetle " is also clearly due to commerce, for it is 

 abundant in all the eastern and Mississippi valley States and 

 thins out westwards as it reaches the great plains. 



In more recent years other Cockroaches have made 



282 



