262 



COLLEGE ZOOLOGY 



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Kissing bug (Hemiptera), 

 vector of Chaga's disease 



Oriental rat flea 

 (Siphonaptera), vector 

 of bubonic plague 



Deer fly (Diptera), 

 vector of tularemia 



Out 



Body louse, "cootie" (Anoplura); 

 vector of typhus, relapsing and 

 trench fevers 



Tsetse fly (Diptera), 

 vector oif African 

 sleeping sickness 



Sand fly (Diptera), 

 vector of kala-azor 

 and oriental sore 



Figure 160. Some insects that transmit human diseases. The figures are not drawn to scale. 



dominal segments; usually two or three long, 

 filiform, segmented, caudal appendages; less 

 than 20 species known from the United States. 

 Ex. Lepisma saccharina (Fig. 159), silver- 

 fish. 



Order 3. Collembola (Gr. kolla, glue; ballo, 

 put). Springtails (Fig. 129). Primitive wing- 

 less insects; chewing or sucking mouth parts; 

 4 segments in antennae; no metamorphosis; 

 usually no tracheae, compound eyes, Mal- 

 pighian tubules, nor tarsi; 6 abdominal seg- 

 ments; springing organ present in most species 



on ventral side of fourth abdominal segment; 

 sticky tubelike projection on ventral surface of 

 first abdominal segment. Ex. Achorutes nivi- 

 cola, snow flea. 



Order 4. Orthoptera (Gr. orthos, straight; 

 pteron, wing). Grasshoppers, etc. Metamor- 

 phosis gradual; chewing mouth parts; typically 

 two pairs of wings; forewings often thickened 

 and parchmentlike, called tegmina (singular, 

 tegmen); hindwings folded like fan beneath 

 forewings; in some, wings vestigial or absent; 

 6 common families as follows: 



