ACARINA PARASITES. 



639 



broad; after a time the legs and proboscis begin to protrude. 

 The body is partially 

 covered by set*, and the 

 'feet terminate in hooks. 

 These stages of the de- 

 velopment of the acarus 

 are exhibited in- fig. 291. 

 The Acarus farinoe, 

 Flour-mite. — This is of 

 occasional occurrence in 

 flour, but is never pre- 

 sent unless it has be- 

 come damaged. Any 

 flour, therefore, contain- 

 ing the animal in ques- 

 tion is in a state unfit 

 for consumption. We 

 believe that it is found 

 more frequently in the 

 flour of the Leguminosce 

 than that of the Gra- 

 minece. 



This acarus differs con- 

 siderably in structure 

 from the Sugar-mite, 

 particularly so in its 

 pennate setee. 



Dr. Burnett esta- 

 blished to his satisfac- 

 tion the following facts : 

 " 1. That though there 

 are single species of pa- 

 rasites peculiar to parti- 

 cular animals, there are 

 others which are found 

 on different species of 

 the same genus; as is 

 the case in the para- 

 sites living on birds of 

 the genus Lams (gulls), Fig. 298 



nnr! thf> rKiirml Wrla nf *' Hippobosca Hirundinis. 2, A'imi.malt 

 dUCl me Qiurnaj DirQo 01 and female, parasites infesting Swallows. 



Fig. 292. — Acarus farina-, Meal-Mite, magni- 

 fied 250 diameters. 



