452 



J. B. JOHNSTON 



bo. 



Fig. 45 Bat, median sagittal section reconstructed from several sections. 

 Note the depth of the neuroporic recess and the two large blood vessels pene- 

 trating the brain to its vicinity. The cells are drawn free-hand. Compare fig- 

 ure 46. 



Fig. 46 Bat, nearly median sagittal section drawn under the Edinger appa- 

 ratus to show the size and arrangement of cells in the paraterminal body and 

 the primordium hippocampi. This section being at one side of the middle plane 

 does not show the depth of the neuroporic recess (compare fig. 45). 



Fig. 47 Bat, parasagittal section to show the relations of the precallosal 

 hippocampus. The section is drawn not far from the median plane, passing 

 through the fornix column of one side. It shows that the anterior pallial com- 

 missure is penetrated by numerous cells of the hippocampal primordium. At 

 h is the club-shaped enlargement of the pre-callosal hippocampus. Magn. 50 

 diam. It is strictly not correct to designate any part of the commissure complex 

 as corpus callosum. The rostral limb contains many hippocampal fibers. It 

 is likely that it differs from the corresponding part of the anterior pallial com- 

 missure in the opossum only in having a somewhat larger numbier of callosal 

 fibers. 



