SKULKERS IN DRY FOOD MATERIALS 445 



for food, notwithstanding that they were securely packed in 

 tin boxes in the factories. A chance lot of unopened biscuit 

 tins, drawn at random from stores at various foreign stations, 

 revealed the fact that the biscuits harboured four different 

 species of Moths 1 and eleven distinct species of Beetles 2 . The 

 authors of this investigation, Messrs Durrant and Beveridge 

 (1913), came to the conclusion that these pests had gained 

 access to the biscuit box before it was sealed up in the factory. 

 But the pests were not necessarily natives of the country 

 where the biscuits were manufactured, for they may have 

 come thither in flour from the ends of the earth. It is no 

 simple chain of events which has distributed Biscuit Beetles 

 and Moths throughout the civilized world. 



SUGAR AND TOBACCO 



Other materials have brought their own pests. Raw 

 sugar imported to this country swarms with minute mites 

 (GlycyphagMs), which set up a slight irritation, known as 

 "Grocers' Itch," on the skin of persons handling the sugar 

 in quantity. Wherever tobacco or cigarettes may go, only 

 too often the Cigarette Beetle (Lasioderma serricorne] 

 accompanies them. 



PEAS AND BEANS 



Peas, Beans, and possibly Lentils also have been the 

 means of contributing to the fauna of Scotland, for each of 

 these harbours its own peculiar pest. While pea-pods are 

 green in the fields, the Pea Beetle (Bruchus pisoruni], a small 

 beetle one-fifth of an inch long, of rusty black colour broken 

 by a white spot on the thorax, lays its eggs upon the pods. 

 The grubs, so soon as they hatch, bore their way through 

 the pod and into the peas, and there they feed, hidden from 

 the eyes of the world. As the pea ripens the larva still 

 continues to feed within, until only a shell, concealing a 

 mature larva, remains. In this safe shelter, the Pea Beetle, 

 a native of North America, has been transported to most 

 civilized countries. It has been reported from several 



1 Ephestia kiihniella, E, cautella, E. elutella, and Corcyra cephalonica. 



" Silvanus surinamensis, Trogoderma sp., Sitodrepa panicea, Lasioderma 

 serricorne, Rhizopertha dominica, Ptinus tectus, Tribolium castaneum, T. 

 confusum, Tenebrioides mauritanicus, Calandra oryzae, and C. granaria. 



