INSECTS IN COMMERCE 141 



which she soon becomes entirely covered with the 

 exception of her sucking mouth, an aperture near 

 the tail end, and two other openings for the 

 admission of air. Opinions vary as to whether 

 the lac is a natural secretion, or whether it is the 

 resinous juice of the tree, which becomes altered 

 in character by being sucked up by the insect 

 after it has caused the sap to flow by piercing the 

 bark. The small branches of the trees become 

 quite encrusted with the lac, and are then cut 

 off and the lac removed and converted into the 

 shellac of commerce. 



The males also form a lac cocoon, but escape 

 by the anal opening on completing their meta- 

 morphosis; and the young, which are hatched 

 within the female cocoon, leave the lac cell in 

 the same way. 



A species of the same family, C. manniparus, 

 inhabits Mount Sinai and produces a kind of 

 thick, red syrup by piercing the bark of the 

 tamarisk trees on which it lives ; it is sweet 

 and rather like honey, and is much eaten by the 

 Arabs and the monks. The syrup overflows the 

 branches and falls to the ground, where it forms 

 into soft sweet cakes, called " Mount Sinai 

 Manna," and it is supposed that this was the 

 manna eaten by the Israelites during their 

 wanderings in the Wilderness. 



Yet another member of the Coccidae (C. ceri- 

 ferns) produces a remarkably fine, hard wax. It 

 is found in China, where it lives principally upon 

 the ash tree. The Chinese use this wax for 

 candles, or to coat those made of inferior wax ; 

 and for sizing paper and textile fabrics. On 



