Page:Proceedings of the Royal Society of London Vol 4.djvu/468

Rh duced into the parietal nucleus of the cell is part of the process which propagates the cell ; that the mode of reproduction of cells is essentially fissiparous, and that the process of assimilation pre- pares them for being cleft.

A pellucid point is described by the author as being " contained in a certain part of the cell-wall, and as representing the situation of a highly pellucid substance, originally having little if any colour." This substance, which he considers as being primogenital and forrh- ative, he denominates hyaline^ and ascribes to it the following pro- perties. It appropriates to itself new matter, thus becoming enlarged ; then divides and subdivides into globules, each of which passes through changes of the same kind. Under certain circumstances, it exhibits a contractile power, and performs the motions called molecular. It is the seat of fecundation, and it is by its successive divisions that properties descend from cell to cell, new properties being continually acquired as new influences are applied ; but the original constitution of the hyaline not being lost. The main pur- pose for which cells are formed is to reproduce the hyaline ; and this they do by effecting the assimilation which prepares it to divide ; such division being thus the essential part of fissiparous generation.

The remaining part of the paper is occupied with a detailed ac- count of these processes as they occur in the development of the ovum, and also in the changes exhibited by the corpuscles of the blood, in which fissiparous reproduction also takes place, and the red blood-discs are converted into fibrin, and thus give origin to the various tissues of the organs. The same theory of fissiparous reproduction he also applies to the formation of the muscular fibre, in connexion wdth his belief that it is composed of a double spiral filament. Contractile cilia, he supposes, are also formed by the elongation of nuclei, the filaments proceeding from them in opposite directions. The author considers, lastly, the subject of the fissipa- rous reproduction of the Infusoria, and particularly of the Volvox globator, the Chlamido-mojias, Baccillaria, Gonium, and the Mona^ dina in general ; and applies the same theory to gemmiparous repro- duction, and to the so-called spontaneous generation of infusoria and parasitic entozoa.

James Meadows Rendel, Esq., was balloted for, and duly elected a Fellow of the Society.

The following papers were read, viz. —

1. "Researches on the Decomposition and Disintegration of Phosphatic Vesical Calculi ; and on the introduction of Chemical