Plate V. 

 Fig. 1[). Cephalic i.late of JJixira. Stage I. Showing the thidveiied areas 

 which form the begiiiiiiug of the optic ganglia, o. gl., and the rostrum, ros.. 

 the rudiments of the chelicerje, clil. and pedipalp.s, pf7/>.. and the lateral 

 groove, hit. gr. 



Fig. 20, Stage II. Showing a slight advance in the differentiation of the 

 optic ganglia and in the development of the rostrum ; also a marked increase 

 in the growth of the pedipalps and chelicer:e. 



