178 
near the former boundaries of pulp cavity, sometimes through- 
out the dentine. The connection and continuation of tubuli 
will be distinctly seen, and traced from primary to secondary 
dentine, the regularity of the primary disappearing in the 
secondary dentine. Slips of glass, Canada balsam, spring 
wooden clamps, or clothes-pins, a spirit lamp, saw, and hone, 
are all that is necessary to prepare specimens. The pitch is 
formed by gently evaporating the balsam over a spirit lamp 
until when cold it becomes hard, and of a brown colour. 
The Homologies of the Dental Plates and Teeth of the 
Proboscidiferous Molluscs. By G. Denis Macdonald, M.D., 
F.R.S. Annals and Mag. Nat. Hist., Feb., 1869. 
Connective Tissue. — Development of Connective Tissue 
in the Placenta. By Prof. Rudolph Maier. Virchow’s 
Archiv, 1st part, 1869. 
On the so-called “ Bindesubstanz ” of the Central Organs 
of the Nervous System. By J. Henle and F. Merkel. 
3 plates. Zeitschrift fur Rat. Med., vol. xxxiv, 1st part. 
Gland. — On the Development and the Structure of the 
Spermatic Particles of Fishes. By Ph. Owsjanikow. Melanges 
Biologiques de V Acad. Imp. St. Petersbourg, September, 1868. 
— The author has sent to us a German abstract of his paper, 
and the original in Russian, with a plate. He discusses the 
views of Kolliker, Schweiger-Seidel, and La Yalette St. 
George. 
General. — Studies on the Nervous, Muscular, and Glan- 
dular System of the Crayfish ( Astacus fluviatilis). By Dr. 
Victor Lemoine. Annales des Sciences Naturelles, 1868. — 
This is an exceedingly careful study of a very common animal, 
and is therefore likely to interest many of our readers. There 
is always something of value to be ascertained by detailed 
study of even these commonest forms. The glandular system 
has received especial attention from M. Lemoine ; and the 
structure of those bodies thought to be the homologue of the 
cement-glands of Cirrhipedes is minutely described. 
The Luminous Organs of Lampyris noctiluca. By Ph. 
Owsjannikow. Mem. de V Acad. Imper. St. Petersbourg, 
tome xi, No. 17. — This is a memoir in German. The re- 
searches of Max Schultze are referred to, but not those of 
Prof. Targione Tozzetti, whose paper we mentioned last 
year. 
The Animal “ Cell ” not essentially different in Function 
from the Vegetable. — In a paper read before the Association 
of German Naturalists, at its last session in Frankfort, on the 
“ Physics of the Cell , ” Herr Wundt stated as follows: — It 
used to be thought that the vegetable cell had to form organic 
