ANALYSIS OF SOME EVOKED SYNAPTIC ACTIVITIES 427 



P''*' *' 



Fig. 1. Golgi-Cox preparations of neurons in suprasylvian (a and b) and 

 anterior sigmoid gyrus (c and d) of 5-hr-old kitten, a. Cluster of medium and 

 large pyramidal neurons. Apical dendrites extend to within 25-50/^ of pial 

 surface. Note absence of lateral branches. Axons of two neurons clearly shown 

 extending downward. Basilar dendrites at this stage are short, thin processes. 

 Band c. Embryonic Cajal-Retzius neurons in molecular layer, d. Giant pyramids 

 in motor cortex with massive apical dendrites, but poorly developed basilar 

 dendrites. Further description in text. 



