BRITISH INSECTS 



ORDER IX. DIPTERA, OR FLIES, MOSQUITOES, 

 MIDGES, AND FLEAS 



Comparatively few entomologists specialise in the 

 insects contained in this important Order, and there 

 are any number of new species to be found for the 

 searching. Many are very small, and only the in- 

 dustrious collector is likely to discover them. One 

 indefatigable worker in our own district — Mr. F. W. 

 Edwards, B.A., F.E.S. — has not only added a large 

 number of new species to our Hertfordshire fauna, but 

 has also put on record several kinds new to Britain. 

 Flies and Fleas, as we may popularly call them, are not 

 alluring in their attractiveness, but are rather despised 

 creatures into whose domestic affairs the average in- 

 dividual takes precious good care not to intrude. How- 

 beit. we must include them here^ so as to carry out our 

 scheme of treatment satisfactorily. They pass through 

 a complete change from egg to imago, the adult has a 

 slender attachment between the head and thorax, and 

 the thorax and abdomen are fused together. The 

 larva is, as a rule, legless, and bears a small head, but 

 this does not hold good with regard to that of the Gnat, 

 which has a large head and well-developed mouth, and 

 other parts of quite a different character. 



The Common Flea {Pulex irritans, Figs. 33 to 36), 

 76 



