120 MARION HINES 
terminal plate, the growth in depth and width is apparent. This 
change is a continuous one and, as far as the evidence presented 
in this paper is concerned, it seems to be one which accompanies 
the intrinsic growth and differentiation of the contiguous struc- 
tures. Certain it is, that following the initial differentiation of 
the septum into matrix and marginal velum and the subsequent 
appearance of the two septal nuclei, the matrix layer becomes 
noticeably poor in cells. The whole seems to be a growth at 
the expense of the cells in situ and not a migration of cells from 
other centers. In the two oldest embryos only, the anterior 
ABBREVIATIONS 
A.ch., area chorioidea 
A.ep., area epithelialis 
A.int., area intercalata 
Ant.com., anterior commissure 
Ang.term., angulus terminalis 
Ang.vent., angulus ventralis 
Ant.l.hyp., anterior lobe of hypophysis 
Bul.olf., bulbus olfactorius 
Cer., cerebellum 
Cor.mam., Corp.mam., corpus mamil- 
lare , 
Cor.str., Corp.str., corpus striatum 
complex 
Cor.str.lat., Corp.str.lat., corpus stri- 
atum laterale 
Cor.str.meéd., Corp.str.med., corpus stri- 
atum mediale 
Def .fas.den., fascia dentata 
Dien., diencephalon 
Dien.r.pl., diencephalic roof plate 
Di-tel.gr., di-telencephalie groove 
Ep.ev., epiphyseal evagination 
Epith., epithalamus 
Fas.den., fascia dentata 
F.b.op.ch., bed of the optic chiasma 
Fil.olf., filasolfactoria 
Fis.hip., fissura hippocampi 
Fis.pr., fissura prima 
For., fornix 
For.int., foramen interventriculare 
Hab., habenula 
Hab.com., habenular commissure 
Hip., hippocampus 
Hypoth., hypothalamus 
Inf., infundibulum 
TIs.cal., islands of Calleja 
Lam.ep., lamina epithelialis 
Lam.ter., Lam.term., lamina terminalis 
Lat.olf.tr., lateral olfactory tract 
Lim.men., limitans meningea 
Man.l., marginal velum 
Mat., matrix 
Mes., Mesen., mesencephalon 
Mes.f.pl., mesencephalic floor plate 
Mes.r.pl., mesencephalic roof plate 
Met., Meten., metencephalon 
Myel., myelencephalon 
_ Neopal., neopallium 
Nuc.ac., nucleus accumbens of Kappers 
Nuc.lat.olf.tr., nucleus lateralis tracti 
olfactorii 
Nuc.lat.sept., nucleus lateralis septi 
Nuc.lent., nucleus lentiformis 
Nuc.med.sept., nucleus medialis septi 
Olf. bulb, olfactory bulb 
Olf.evag., evagination of olfactory 
bulb 
Op.c., optic chiasma 
Op.evag., Opt.evag., optic evagination 
Op.s., Op.st., optic s talk 
Par.ar., paraphysea, arch 
Par.p., paraphyseal pouch 
p.c., pars crassa of lamina terminalis 
P.com., Post.com., posterior commissure 
