1883. ] Recent Literature. 63 
united to the atlas, and movement is limited to that possible be- 
tween the adjoining facets of the odontoid and atlas, but in E/seya 
latisternum the odontoid process is distinct. On the other hand, 
Cycloderma aubryi among the Trionychidz has these parts united 
to that any extended movement seems impossible. 
M. Vaillant does not consider the retraction or non-retraction 
of the neck a leading character, and prefers to keep the usual 
classification into the three great families of Cheloniida, Triony- 
chide, and Testudinide. The first of these includes the Thalassi- 
ans and the Chelodinz (pleuroderes), the second the Trionychide 
only; the third the Chelydina (pleuroderes) and Chersemydina, 
which last group embraces the incompletely cryptodere Chely- 
dre and the truly cryptodere Testudinez. 
Whatever difference of opinion there may be upon the value 
of certain characters in classification, we will not deny the force 
of M. Vaillant’s argument, which is as follows: 
“ When we consider that animals as intimately related as are 
Testudo pusilla and Pyxis arachnoides present really important dif- 
ferences in the constitution of the cervical part of the back bone, 
we cannot but place a great distinction between genera established 
from the elements at the disposal of the palzontologist and those 
established by the more complete study of the whole structure 
of living animals.” 
ALLEN’s Human Anatomy.'—The object of the author of this 
work is to present the facts of human anatomy in the manner 
best suited to the requirements of the student and practitioner of 
medicine. It is, in fact, intended to be a physician’s human an- 
atomy, not one for the use of the scientist or the surgeon, for one 
or the other of whom most works upon anatomy have been writ- 
ten. As surgical and general medical practice are not separated 
from each other in this country to the same extent that they are 
in Europe, the author believes rightly that there is room for a 
work which shall accurately and concisely express the present 
state of anatomical science, including every application thereof 
needed by the physician. 
; e form and construction of the human body, the variations 
in the condition of the various organs within the limits of health, 
the relations of the parts to each other, both topographically and 
clinically ; the uses of the organs, and the nature and general be- 
havior of morbid processes with the manner in which they are 
modified by locality, should all be known to the physician, and 
will obtain ample treatment in this work. Aware that some of 
these desiderata trench upon physiology, Dr. Allen engages only 
to treat of them from an anatomical point of view. Those scien- 
tists who are not physicians will be pleased to find that the work 
z | System of Human Anatomy, including its medical and surgical relations. By 
Harrison Allen, M.D. Philadelphia: Henry C. Lea’s Son & Ce., 1882. 
T 
