THE FAUNA OF THE CACAO FIELD 121 



When left to maturity (seldom allowed in man) it pupates 

 and readily leaves the skin of its host, the wound healing 

 quickly. Finding one of these insects in a rat (Loncheres 

 guiana), the author kept the animal in a cage until the 

 insect developed, secured the pupse, and hatched from it 

 a large two-winged fly, which was afterwards named as 

 Cutiterebra funebris, new species {Annals and Mag. Nat. 

 History, Series 6, vol. xv. May 1895). When an overseer 

 or other member of the staff becomes infected with this fly, 

 he should at once have it removed. The insect, however, 

 need not be feared, if due attention is given to keep all 

 parts of the body well covered, when resting or sleeping 

 in the open, which prevents the ova being deposited. 

 It is not common except in a few woodland districts. 



No. 25. " Spider Web " Insect {Embia Urichii and 

 Embia trinitatis). — ^These are insects which form white 

 webs on cacao and other trees. The insect is a peculiar 

 one, and belongs to the Embidce, under which only a single 

 genus is known. It much resembles in form the European 

 " earwig " {Forficula). The insect covers the bark with a 

 thick matted white web, which is nearly opaque, but 

 through which may be seen the thicker channels, ways or 

 paths, used by the insects. The web covers, at times, sur- 

 faces eight to ten inches square, while at others its diameter 

 will not be more than three inches. They frequently 

 shift their web, and the place of their abode probably 

 depends much on the food-supply present. The web affords 

 protection to them and also their families, which are raised 

 beneath it in a communistic manner. It has been noted 

 that newly made webs are generally constructed over areas 

 covered by lichens, mosses, fungi, and scale insects. An 

 examination of a deserted web shows that in every case 

 the surface of the bark has been beautifully cleared of all 

 vegetable and animal matter, which is strong evidence 

 that the insect is a bark scavenger, and that it does a 

 considerable amount of good. The writer has observed 

 the method of spinning from a collection kept in captivity, 

 and fed upon similar matter as that which is found beneath 



