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TEXT-BOOK OF ENTOMOLOGY 



growths may be in general 

 termed apodemes. There 

 are similar structures in 

 Crustacea and also in Limu- 

 lus; but Sharp restricts this 

 term to minute projections 

 in beetles (Goliathus) situ- 

 ated at the sides of the 

 thorax near the wings. (In- 

 secta, p. 103, Fig. 57.) The 

 internal processes arising 

 from the sternal region have 

 been called endosternites. 



The acetabula. These are 

 the cavities in which the 

 legs are inserted. They are 

 situated on each side of the 

 posterior part of the ster- 

 num, in each of the thoracic 

 segments. They are, in gen- 

 eral, formed by an approxi- 

 mation of the sternum and 

 epimerum, and sometimes, 

 also, of the episternum, as in 

 Dyticus (Fig. 97, A). This 

 consolidation of parts, says 

 Newport, gives an amazing 

 increase of strength to the 

 segments, and is one of the 

 circumstances which enables 

 the insect to exert an aston- 

 ishing degree of muscular 

 power. 



Fio. 101. Internal skeleton of f.it- 

 eai/ti cft-ruti. <?. head : A, antenna; 

 /, mandible ; '/, meiitimi ; 2, 4, tendons 

 'of mandible: /. n. t. parts of the tento- 

 rium ; 8 e, labial muscles. Thorax: 

 '2. prothorax ; 3, 4. meso- and nietathorax 

 fused solidly together; 8 /% acetabulum 

 of prothorax, Into which the coxa is Inserted; 2 *, sternum; 3#," aoctabtilnm of mesotlmrax, 

 4r, of nietathorax; 3 s, mesothoracic sternum fused with that of the nietathorax (4(/); 4 ,v, 

 apodeine. After Newport. 



