486 J. T. WILSON AND J. P. HILL. 
tions somewhat similar epithelial cell-masses are seen still 
connected with the Malpighian layer of the epithelium. 
We cannot give a positive opinion respecting the signifi- 
cance of these more or less isolated cell-groups. Either they 
are partially strangled epithelial ingrowths, such as we shall 
later on have occasion to refer to as dipping more or less 
deeply into the connective tissue from the deep surface of that 
lamina which forms the Anlage of the lip-furrow (labio- 
alveolar furrow) ; or else they may have to be interpreted as 
degenerated remains of the connections of a first milk incisor. 
If the latter, then the irregular area with which they are related 
must be interpreted as forming, morphologically, a part of the 
labial surface of the original dental lamina, whose basal part 
has, as it were, opened out towards the mouth cavity. We 
think that consideration of the appended figs. 43—46 will 
support this as at all events a plausible explanation. 
It will be remembered that in Stage 111 no rudiment of 
di+ was found. But the connection of the dental lamina (at 
its first incisor enlargement) with the oral epithelium was a 
very broad one, and, in the reduction to its present dimen- 
sions, it might well have left cellular vestiges of a rudimen- 
tary di+, stranded, as it were, on the labial side of the now re- 
latively constricted base of the proper dental lamina. 
In fig. 45 the residual dental lamina (rdl.) in the region of 
74 is well seen. Its fundus is distinctly enlarged (‘‘kolbig”), 
but it is merely the thickened free margin of the continuous 
lamina seen in front in fig. 43 and the succeeding figures. 
Behind this point, indeed (i.e. fig. 45), it loses its independ- 
ence for a few sections, when it is more intimately fused with 
the side of the enamel-organ of é+ (fig. 46), but almost imme- 
diately it again extricates itself as a free but less prominent 
residual lamina. Shortly behind this again, opposite the 
posterior part of 24+, the lamina is practically suppressed 
altogether. Traces of its former presence remain in the shape 
of slight and inconstant cellular projections from the oral epi- 
thelium, and from the lingual aspect of the enamel-organ of i+, 
respectively. 
