262 R. I. FOCOCK. 



witli caustic polasli, to show the continuity of its supporting chitinous strands 

 witli those of the prosternal plate (p'S.), which is wedged in between tlie 

 coxje of tlie a|)pendages of the third |)air and its attaclinient to the sternal 

 membrane (/«.), between the third and fourth somites of the prosoma; Ls., left 

 bar of the eiitosternite, which expands at the free extremity to form with its 

 fellow of the opposite side a supporting channel (Al.) for the alimentary canal. 

 Fig. 27. — Lower extremity of the two pillars of the entosternile of 

 Gal codes arabs, to siiow this articulation (-/.) with the prosternal plate 

 (prs.), its union with the sternal membrane (w.) ; cox., coxa of appendage of 

 third pair. 



