78 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 98 



nerve ganglia also show to advantage. The ventral ganglionic 

 thickenings are no longer evident on the surface. A parasagittal 

 section of this same embryo is shown in figure 26. X H5- 



Fig. 88. Parasagittal section through the head region of a Ctcnocephalidcs felis 

 embryo at a stage similar to that shown in figures 26 and 87 showing 

 the supraoesophageal and suboesophageal ganglia connected by the 

 circumoesophageal connective of the side. The lateral nature of the 

 section is further indicated by the lack of transverse commissural 

 tracts such as appear in the ganglia shown in figure 85. The 

 definitive nature of the mandible is also evident in this figure. X 400- 



Fig. 89. Portion of a sagittal section through a late embryo of Ctcnocephalidcs 

 felis showing the gonad cut longitudinally, revealing the prominent 

 germ cells inside it. X 400. 



Fig. go. A similar section to that shown in figure 89 but showing the anlage 

 of the genital duct leading posteriorly from the gonad. X 400. 



