3o8 Susanna Phelps Gage 



Fig. 23. Through the hypophysis, infundibuhim and saccus, and 

 more cephalic portion of the endolymphatic sac. 



Fig. 24. Shows the wide dorsal union of the geminums, the layers in 

 the cinerea, and the relations of the branches of the 5th and 7th nerve 

 as they pass to the gasserian ganglion. 



Fig. 25. Shows the relation of the nerves at the level of the origin of 

 the 5th and the lateral wing of cinerea extending to the surface of the 

 epencephal. (cf. Fig. 82). 



Fig. 26. Through the cerebellum and 4th nerve, shows the relation of 

 the lateral recesses of the epicoele to the endolymphatic sac. 



Fig. 27. Shows the cavities of the metaplexus and their relation to 

 the endolymphatic sacs which meet near the meson. 



Fig. 28. The process of a bone upon the meson is surrounded by 

 dura and overlies a much constricted portion of the plexus, the medulla 

 ajjproaching the dorsimeson in the vicinity of the loth nerve, (cf. 

 Fig. 93 x). The ganglion of the loth is partially divided, the more 

 dorsal portion receiving the 9th nerve. 



Fig. 29. Section cephalad of the metapore. 



Fig. 30. At the metapore. 



Fig. 31. Caudad of the metapore. 



Fig. 32-33. Show the rapid flattening of the myel. 



Fig. 35. From another series. Shows a dorsal union of the endolym- 

 phatic sacs, at the level of figure 27. 



PLATE IV. 



Fig. 35-40. Frontal sections of the brain of an adult, male, diemycty- 

 lus 7.5 cm. long, stained in haematoxylin. At the level shown by corre- 

 sponding numbers in figure 6. X about 10. 



Fig. 35. Dorsad of the portae, shows the arrangement of pockets in 

 the metaplexus (p. 267) and the change of direction in the rhino- and 

 paracoeles. 



Fig. 36, Shows the relation of the cavities here interrupted by the 

 caudal wall of the geminums. 



Fig. 37. Shows the ventral dip of the rhinoccele. 



Fig. 38. Shows the crista and the relative position of nerves. 



Fig. 39. The nerves are a composite from three sections. 



Fig. 40. Shows the base of the brain in relation of the parts of the 

 left side, including i, 2, 3, the pockets from the skin which develop in 

 the adult male (Fig. i) and receive branches of the 7th. x (Fig. i) 

 an unidentified body. 



Fig. 41. An enlargement of Fig. 35. X about 60. Shows the rela- 

 tion of the two roots to the olfactory nerve, a branch of the 5th cross- 

 ing it on its way to the intermaxillary gland ; the relation of pia to the 

 nerve roots ; the continuity of ectal and ental cinerea from the tip of 

 the rhinoccele ; the scattered cells of the callosal eminence. 



