88 MIUNTE STRUCTURE OF THE BRAIN AND CORD OF ARACHNIDS. 



FIG. 68. 



FIGS. 67 and 68. A series of sections of the first branchial neuromere of an adult Limulus, showing the location 

 of the principal cell clusters, commissures, fiber tracts, lemmatochord, and central canal. The numbers 66 to 138 

 indicate the serial numbers of the sections. 



