LIMITS OF HEREDITARY CONTROL 891 
exactly the ‘mirror image’ of the double scute in the third band 
of foetus 1. 
These facts may indicate various degrees of imperfect heredi- 
tary control in connection with the localization of these minute 
‘abnormalities,’ but if this be the case we are dealing with a state 
of affairs too complex to admit of solution with the present 
material. 
There are several other sets which exhibit scute ‘abnormalities.’ 
These may for convenience be brought together into a compact 
table (14). Here the number of the double or incomplete ele- 
ments in the various columns refers to the position of each in the 
band; ‘D’ indicates double scute and ‘S’ incomplete or split 
scute: 
Although in the members of these sets the double or incomplete 
elements would appear to occur almost at random, so far as their 
position within the nine bands is concerned, there are some cases 
in which, within a given pair at least, the hereditary control is 
fairly obvious. Table 14 further indicates that a close morpho- 
logical relationship exists between the two types of ‘abnormality’ 
and that they may readily be imagined to have a common hered- 
TABLE 14 
Showing the distribution of double and split scutes in the 20 sets of foetuses 
BAND 
SET FOETUS | im re eae 7 mn a3 
1 2 3 4 5 6 7 8 9 
Tis prey eee 5D | | | 
sh ante } Tiles | 58D | | 
Eyer es | yee 
oe emer ie | 
iIneeion wees | | 46D | 
I | 9D | | | 
DIGE ect II | | 25D | 
1100 ee A he | 9D | 
ja entree eee | 35 
a eae Eeeaeren ey | | | | 13D 
I ae 25D | 54D | | 
Be ode FE matt | 60D 
[Us Witieenec vce a | | | GOS 
sistas ate TIE... ee. | 11D | 
