ON THE FREQUENCY OF ABNORMALITIES IN 
CONNECTION WITH THE POSTCAVAL VEIN 
AND ITS TRIBUTARIES IN THE DO- 
MESTIC CAT (FELIS DOMESTICA). 
Ci F, We McCLUKE. 
VARIATIONS of the postcaval vein and its tributaries are not 
of unusual occurrence, as is attested by the considerable litera- 
ture on-this subject. It is also generally conceded that these 
variations from the normal condition, to whatever cause they 
may be due, occur with greater frequency among domesticated 
animals than among those living in the wild state. 
The object of the present paper is to emphasize especially 
the frequency with which such venous abnormalities may occur 
in a given number of individuals of the domestic cat (Felis 
domestica). 
During the last five years the writer has observed that varia- 
tions of the venous system, of some sort or another, occur with 
great frequency in the domestic cat; and in 1898—99 twenty- 
five cats dissected by students in the Princeton Laboratory 
were more carefully examined for such variations, with the 
following results : a 
In only ten of the twenty-five examined was the venous sys- 
tem apparently normal, while in 60 per cent, or in fifteen of 
the cats, thirty-three distinct abnormalities were met with in 
Connection with the postcava and its tributaries. These, for 
descriptive purposes, have been grouped in the following table 
under five types.! ! 
The cats in which these abnormalities were found were 
chosen at random from those brought into the Laboratory and 
! The figures represent the actual size of the preparations. The veins are in 
black and the arteries shaded. The numbering is the same for all of the figures. 
Many of the smaller arteries and veins have been omitted from the drawings. 
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