TICKS AND FLEAS. 



PUPIPARA 



This group is sometimes given the rank of Suborder. Its 

 members are all ectoparasites, that is, they live on, but not 

 in, their hosts. They are called Pupipara because the 

 larvae live inside the mother until they are ready to pupate 

 or have already done so. The wings are often vestigal or 

 wanting. The}'- are probably degenerate Acalypterates. 



The HippOBOScnxE (Plate LXXI) are parasitic upon 

 birds or mammals. The more commonly observed of the 

 winged species belong to Olfersia and live on hawks and 

 owls. A wingless species is the sheep-tick, Melophagus 

 ovinus. 



Members of the family NYCTERIBIID^E, also of STRE- 

 BLHXE, usually have no wings, although the halteres are 

 retained. Almost without exception, they are parasitic 

 on bats. 



SUCTORIA 



The adult Fleas are small, wingless, laterally com- 

 pressed, jumping, sucking insects which are parasitic upon 

 warm-blooded animals including man. The larvae (Plate 

 LXXI) are worm-like; they live in rubbish and dust, such 

 as accumulates at the edges of carpets and in the folds of 

 upholstery. The pupas are enclosed in cocoons. The 

 family PULICID/E contains the common Dog-flea, Cteno- 

 cephalus cants; the usually rare (with us) Human-flea, 

 Pulex irritans (thorax and head shown in Plate LXXI); 

 and a Rat-flea, Ceratophyllns fasciatus, which transmits 

 plague in temperate regions. The Jigger-flea or Chigoe, 

 Dermatophilus penetrans, of the DERMATOPHILID/E, is 

 confused with the Jigger or Chigger, which is a small red 

 Mite and also burrows into human skin. It infests domes- 

 tic animals and birds, as well as man. The male feeds 

 externally but the female works her way under the skin, 

 causing a serious ulcer through which the eggs are released. 



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