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- made between the respiration of frogs and turtles, proves to be un- 
- founded,—and the abdominal muscles, which in other air-breathing ver- 
__ tebrates are expirat ry, become inspiratory in the turtles, while the pre- 
Botany and Zoology. 141 
2) 
2. Researches upon the Anatomy and Physiology of Respiration in the 
Chelonia ; by S. Wetr Mircaitt, M.D., and Gzorce R. Morenouss, 
M.D, (Smithsonian Contributions to Knowledge, xiii, 169.)—This memoir 
is one of great interest, not only on account of the admirable manner in 
which the results have been worked out, and the valuable contribution 
which they are to physiology, but as showing how the labors of a carefu 
and truthful observer may pass for more than a half of a century negleet- 
ed, until, falling under theaotice of those who know how to appreciate 
em, the place which is their due is claimed for them in the history of 
science, 
The authors have made a thorough demonstration of the manner in 
which the respiratory movements are executed in turtles, and have shown 
that, with one exception, all writers on the subject from Malpighi to 
Agassiz, including no less authorities than Cuvier, Johannes Muller, and 
ine-Edwards, have fallen into error. The mechanism of breathing in 
these animals, as described by naturalists, has been supposed to be as 
h 
by the raising of the hyoid, air is driven from the mouth through the 
glottis and trachea into the lungs, when inspiration is completed; expira- 
tion is effected by the contraction of the abdominal muscles, and the 
consequent compression of the lungs. This is all wrong. 
cave during expiration, the hyoid apparatus all the while being motion- 
us tHe) parison which, since the days of Malpighi, has been 
sumed homologue o¥ the diaphragm is the true muscle of expiration. 
