Mr Heape, Notes on the Proportion of the Sexes in Dogs. 147 
I have taken advantage of the fact that, in the Schedules 
returned to me, the performance of each sire and bitch is recorded 
for each litter, to test the tendency of individual male and female 
parents to produce a marked proportion of offspring of one sex. 
Only those cases are recorded in which the sire or the bitch have 
been concerned with four or more litters and the results are 
compared with the average obtained for the breed to which each 
animal belongs (Table X). 
Of the six Basset hound sires one has got 44 fewer and one 
5G more dog pups than the average, whilst the four bitches show 
great variation and one has 122 dog pups above the average. 
Of the four Bloodhound sires one has 52 more and two others 
38 and 26 fewer dog pups than the average ; there are no bitches 
of this class recorded as having produced four litters. 
A single dog and bitch among Collies produce about the 
average. 
Of Mastiffs there is one sire responsible for more than half of 
the whole litters recorded in Table VII for that breed, and the 
low percentage of dog pups he is responsible for dominates the 
total results. A single Mastiff bitch, on the other hand, produces 
56 more dog pups than the average for the breed. 
Only one Scotch Terrier sire is recorded with about the 
average of dog pups, while a single bitch falls short in her produce 
of dogs by 34. 
Only one Skye Terrier bitch is recorded and the proportion of 
males she produced was 333 above the average. 
Of Irish Terriers there is one sire and two bitches, the latter 
with a proportion of dog pups of 60 less and 188 more than the 
average, while the former has 28 to his credit. 
Dachshunds again are very variable, especially the sires, of 
which there are three, varying from 88 - 8 to 17027 dogs, while the 
three bitches show variation from lOO'O to 1444 dog pups, the 
average for the breed being 122‘28. 
Amongst Dandie-dinmonts two sires give extraordinarily low 
results, 34 and 18 less than the exceptionally low average for the 
breed (102 82); the single bitch whose produce is recorded shows 
14 more than the average of dog pups. 
Thus of the total number of litters (297) recorded in Table VII, 
146 (or 49T6 °/o) are got by 19 sires, and 70 (or 23'57 u /«) borne by 
14 bitches. 
Of these 19 sires, 15 show a variation of 10, 9 a variation of 
20, 7 of 30, and 2 of 50 from the average. Of the 14 bitches, 
12 show a variation of 10, 10 of 20, 6 of 30, and 5 of 50 from the 
average. It is therefore clear that the bitches show a much 
higher proportion of variation than the sires. 
The numbers concerned are of course too small to allow of 
