142 Mr Heape, Notes on the Proportion of the Sexes in Dogs. 
sponsible for the redaction, and as the other breeds show very 
similar results there is good reason to believe that the litters 
recorded in the Kennel Register very generally include all the 
pups born. 
If this assumption is correct a comparison of the proportion 
of dog and bitch pups born is of increased interest. 
In both classes, both Large dogs and Terriers, the proportion 
of dogs born is considerably greater in the Schedule than in the 
Kennel Register records, namely for Large dogs 7 '42, for Terriers 
9'3, and for the totals 7 - 72 greater. The difference being 
specially marked for Terriers. 
Taking particular breeds in the Schedules, as compared with 
the same in the Kennel Register, Bloodhounds show + 3'83, 
Collies + 1'81, Mastiffs — 9'82, Scotch Terriers + 23'22, Irish 
Terriers + 24T2, Dandie-dinmonts — 12ol 
The only breeds in the Schedules showing fewer dog than 
bitch pups are Mastiffs with 97 '73 and various Small dogs with 
7L43 dogs per 100 bitches; while in the Kennel Register, Setters 
96'43, and Bedlington Terriers 96T5, are the only breeds in that 
category. 
In the case of neither the Mastiffs, Setters, or Bedlington 
Terriers can it be claimed that either fertility or the number of 
litters included in the calculation, affect the proportion of the 
sexes produced. 
From the totals it appears that the Schedules show a greater 
proportion of dog pups than either the Greyhound Stud Book or 
the Kennel Register, and, while making allowance for racial 
variation, it would seem probable that the opinion expressed by 
Greyhound breeders, recorded by Darwin, that bitches are pro- 
duced in excess, is not true ; on the contrary such difference as 
does exist in these three returns would indicate that, as in human 
beings, young males are more difficult to rear than females, and 
that there is an excess of deaths among young dog pups. 
The Schedule returns again show that, taken as a whole, the 
larger breeds of dogs with the greater fertility produce a larger 
proportion of dog pups. 
The difference is not so great as was shown by the Kennel 
Register records, being only 2'63, but still it exists. No such 
regular difference, however, can be shown for individual breeds 
in Table VII, and it seems probable there are not a sufficient 
number of litters among these Schedules to admit of a fair com- 
parison with those detailed in Table IV on this point. 
As regards the effect of in-breeding on the proportion of the 
sexes produced, the most marked instance among my records is 
that of Basset hounds. A very large proportion of the litters 
recorded for this breed came from one kennel, that of the late 
