123. 
upon the dorsal aspect of the cerebrum, they both make the remark- 
able and quite incomprehensible statement that the Fascia dentata 
lies upon the lateral aspect of the hippocampus proper. KÖPPpeEn !) 
does not refer to the Fascia dentata at all. Britu?), however, pro- 
perly locates it on the mesial hemisphere wall; but would appear to 
make it, as well as the hippocampus, far too extensive. ADOLF MEYER’) 
would appear to locate it accurately, if somewhat doubtfully. Her- 
RICK *) signally failed to recognise the cephalic extremity of the hippo- 
campus in reptiles, and called this part of the hippocampal formation 
“fronto-median lobe”. The corresponding part of the hippocampal 
commissure he called “corpus callosum”. 
In the evolution of the mammal from the reptile the whole hippo- 
campal formation becomes relegated to the mesial hemisphere wall by 
the growing pallium. The continuation of this process of pallial ex- 
tension on the one side and the rapid growth of the Stratum granu- 
Hippocampus 
Pallium ae E 
Fissura 
hippocampi 
Fascia dentata 
Precommissural 
area 
Fig. 2. Scheme of{T. G. hippocampal formation of Ornithorhynchus through 
the region corresponding to fig. 1. ;5% 
1) “Zur Anatomie des Eidechsengehirnes’. Morphologische Arbeiten, 
herausg. von G. ScHwALBE, Bd. I. 
2) “The true Homology of the mesal Portion of the hemispheric Ve- 
sicle of the Sauropsida“. Medical Record, March 29, 1890. 
3) “Ueber das Vorderhirn einiger Reptilien”. Zeitschr. f. wiss. Zoo- 
logie, Bd. LVI, p. 63. 
4) “Topography and Histology of the Brain of certain Reptiles”. 
Journal of Comp. Neurology, V. I, March 1891. 
9g * 
