AUTHOR’S ABSTRACT OF THIS PAPER ISSUED 
BY THE BIBLIOGRAPHIC SERVICE, JULY 12 
SOME MORPHOLOGICAL CHANGES FOR ADAPTATION 
IN THE MOLE 
JAMES ROLLIN SLONAKER 
Physiology Department, Stanford University 
FOUR PLATES (TWENTY-FOUR FIGURES) 
The mole, owing to its subterranean habits, has developed 
some very remarkable morphological changes in some of its ana- 
tomical parts which specially adapt it to its environment. Some 
of these changes show marked differences from the general mam- 
malian type. 
The most prominent changes are: the degeneration of the eyes; 
the great increase in size of the pectoral girdle and anterior limbs; 
and a relative reduction in the pelvic girdle and posterior limbs, 
accompanied by a shifting in position of the urogenital canal 
and the posterior part of the alimentary tract with reference to 
the pelvic arch. 
The various comparative anatomies and special articles which 
I have been able to examine have described some of the modifica- 
tions as found in the European mole, but have been very meager 
in the discussion of the relations of these modifications. 
The purpose of this paper is twofold: First, to bring together 
in as compact a form as possible the results of former investiga- 
tors which are now scattered promiscuously and often in.a more 
or less fragmentary manner throughout the literature and to 
correlate these results with the present investigation. Second, 
to describe these modifications in the American mole and to 
correlate them as far as possible with each other and with the 
habits and environment of this animal. 
All the figures in this article were made from the American 
mole, Scalops aquaticus, of the Mississippi Valley. In the de- 
scription some other species are included, especially that of the 
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JOURNAL OF MORPHOLOGY, VOL. 34, NO. 2 
