INDEX 
TO THE 
PHILOSOPHICAL TRANSACTIOxNS 
FOR THE YEAR 1853. 
A. 
Adams (J. C., Esq.). On the Secular Variation of the Moon’s Mean Motion, 397. 
Aoathocles, eclipse of, 187. 
Airy (G. B., Esq., Astron. Roy.). On the Eclipses of Agathocles, Thales and Xerxes, 179. 
Allman (Ur. James). On the Anatomy and Physiology of Cordylophora, a contribution to our 
history of Tubularian Zoophytes, 367. 
Amphibia, on the impregnation of the ovum of, 233. 1. Comparison of the vitality of the ovum 
and the spermatozoon, 234. 2. Evolution of vitality in the spermatozoon and ovum, 237. 
3. Vitality of the ovum, 239. 4. Endosmosis of the egg in reference to its vitality, 242. 
5. Quantity of spermatozoa essential to fecundation, 245. 6. Tests of fecundation, 246. 
7. Partial or incomplete fecundation, 247. 8. Deficiency of fecundatory influence, ibid. 
9. Portion of the yelk most susceptible of fecundation, 251. 10. Excess of fecundatory in- 
fluence, 253. 11. Deficiency and excess of fecundatory influence compared, 256. 12. The 
motion of the spermatozoon in relation to its function, 259. 13. Penetration by the sperma- 
tozoon in effecting fecundation, 266. 14. Nature of the influence of the spermatozoon, 281. 
Archetype of the Cephalous Mollusca, 44. 
Atlanta, anatomy of, 36. 
B. 
Bakerian Lecture, 549. 
Balloon ascents, meteorological observations in, 312. 
Birds, structure and development of the liver in, 11. 
Bone, on the structure and development of, 109. Haversian and other canals of bone, 110. 
Laminae, 112. Lacunae, 115. Haversian systems, 117. Ossified cartilage of joints, 118. 
Ossified lacunal cells, 119. Bone tissue, 120. Development of bone, 123. Growth of 
bone, 130. 
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