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Nachdruck verboten. 
Pelvic and horseshoe kidneys in the domestic cat. 
By CuarLes E. Jonnson, Ph. D. 
From the Laboratory of Comparative Anatomy of Vertebrates, Department of 
Animal Biology, University of Minnesota, Minneopolis, U.S.A. 
With 3 figures. 
Dystopy of the kidneys and so-called horseshoe kidneys have long 
been known in human anatomy as the most frequent anomalies of 
the renal organs met with, and the literature on the subject is ex- 
tensive. Numerous cases have been described, and the probable causes 
and embryonic processes invulved have also been discussed. I have 
been unable, however, in the literature at hand, to find any reference 
to the occurrence of such abnormalities in mammals other than the 
human species. They doubtless occasionally occur among most or all 
mammalian species and have the same or similar causes underlying. 
The forms available for laboratory dissection, or so employed, are as 
a rule limited in kind and often in number, and the anomalies here 
referred to are sufficiently rare to render observed cases, in any 
event, few. 
During the last seven years the common house-cat (Felis domes- 
tica) has been the principal mammalian type used for dissection in 
the classes in comparative vertebrate anatomy in this laboratory. 
Approximately four hundred cats have been dissected within this 
period, and among this number only two renal anomalies have come 
to our notice. One of these is a case of pelvic kidney, the other is an 
unusual form presenting a horseshoe type combined with an anomaly 
of a different character. 
It is not the purpose here to review the literature on this sub- 
ject, but before proceeding to the description of the specimens it may 
