MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



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almost oiitiivly thirk chostmit. The two dorsul prothoracic tubercles are now very short, not so 

 hig-h as broad, and end in a jiroup of rounded conical spinules; those on the side of tlie same 



Fig. 16.— Armature of Eacks impcrialis. 



segment having the same general .shape. T/ie second and third thoi'acic segments, with the dorsal 

 horns, now much as in the fidl-grou-n larm, though a little slenderer; length, 5 mm.; they are 



