LOCTJST 177 



Make out the following parts : 

 The first segment forming 



1. The protliorax. — What is its shape as seen 



from above? From the side? Hovy is it con- 

 nected to the parts preceding and following it ? 

 How does it compare in size with the other seg- 

 ments of the thorax? Does it bear append- 

 ages? Notice the expansion, the pronotum, 

 of its tergal portion. Try to make out the fol- 

 lowing plates composing the prothorax : on the 

 dorsal side, beginning at the anterior end, the 

 prsescutum, the scutum, the scutellum, and 

 the postscutellum; on the ventral side, parts 

 corresponding to the sternum of the lobster, a 

 soft, flexible membrane with a posterior hard- 

 ened piece. Note the hairy tubercle, also at the 

 side in the membranes connecting the protho- 

 rax and the mesothorax, the opening or spira- 

 cle. Examine the legs. Number? Color? 

 Position ? To what parts are they attached ? 

 In what direction do the joints bend ? Exam- 

 ine a leg carefully and make out the following 

 parts : coxa, trochanter, femur, tibia, and 

 tarsus or foot. Study carefully the structure 

 of each part. Draw one of the legs. 



Draw the prothorax, showing dorsal, ventral, 

 and side views. 



Examine the second joint or 



2. The mesothorax. — Shape? Connections? "What 



appendages does it bear? How are they situ- 

 ated? Does this segment bear any spiracles? 

 Compare in all respects with the prothorax. 

 Find the two side plates, the episternum in 

 front and the epimerou behind, comprising 

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