Vertebroid Homologies of the Cranium in Vertebralia. 49 
number of other animals, but that they continue to live, still 
preserving the power of producing fresh generations." This 
may hold good for some Infusoria, but it does not seem to 
hold for Ophrydium, because the liberation of the spherical 
vesicles is not effected by any other means than the total 
disintegration of the body of the parent animal — thus, we 
would think, resembling the process in those animals in 
which the deposition of ova is the last act of their existence. 
I would only further remark, that we may consider — 1st, 
That true reproduction does take place in the Infusoria, 
as pointed out by Dr Balbiani ; 2d, That the nucleus plays 
an important part in this process, furnishing the yolk- 
masses which are afterwards developed in the spherical 
vesicles, which are in this case the young Ophrydia ; Sd, 
That there is an alternation of generation with fission ; 4^7^, 
That the masses are the entire product of a single spherical 
vesicle, which we must regard as an ovum ; and, btli, That 
we may suppose that many of the free so-called Infusoria 
are the larval or imperfect forms of the true or fixed ones. 
Wednesday, March 25, 1863. —James M'Bain, M.D., R.N., President, 
in the Chair. 
The following Donations to the Library were laid on the table, aiu) 
thants voted to the Donors : — 
1. Proceedings of the Royal Society, London, Nos. 51 and 52. Vol. 
Xn. — From the Society. 2. Transactions of the Royal Irish Academy. 
Part 2, Vol. XXIV. ; Science, 1862.— From the Academy. 3. Jahr- 
buch der Kaiserlich, Koniglichen Geologischen Reichsanstalt, 1861 and 
1862; XII. Band. Nro. 3, Mai, Jun., Jul., Aug., 1862.— From the 
I. R. Geological Institute of Austria. 4. Transactions of the Botani- 
cal Society, Edinburgh. Part 2, Vol. VII., 1862.— From the Society. 
5. Canadian Journal of Industry, Science, and Art, New Series. No, 
42, November 1862. — From the Canadian Institute, Toronto. 
The following Communications were read :-— 
I. Notes on some Surgical Homologies. By A. M'K. Edwards, Esq. 
II. On the Vertebroid Homologies of the Cranium in Vertebralia or 
Osteozoa, and the analogous Homologies of the Annulozoa, or Arti- 
culata. By William Macdonald, M.D., Professor of Natural 
History, St Andrews. (With Table.) 
Ever since the promulgation of the grand and independent 
inspirations of Goethe and Oken on viewing the bleacked 
VOL. Ill, Gr 
