on the above-mentioned proposition^, the author concludes his paper with the following sentence : —
" The several partial theories of philosophers, as far oji concerns the leading facts on which they are based, are contained in the sim- ple principles here developed : thus, the theory of universal gravity is here carried out to its ultimatum ; Newton and Boscovich's theo- ries of alternate attractions and repulsions are derived from facts which depend on the alternate atmospheres, and neutral spaces of tenacious atoms ; Sir Humphry- Davy's theory of electrical energies, Dr. Dalton's atomic theory, and the theory of the diffusion of gases, Dr. Black's theory of latent heat, Gay-Lussac's theory of volumes, Newton's theory of light, or the theor}" of the emission of light, the undulator}^ theory, and ven;- many others are here united in the most simple principles, which are, therefore, strongly recommended to the notice of philosophers."
6. " On the Organs of Reproduction, and on the Developement of the Mvriapoda." Bv Georsre Newport, Esq. Communicated bv P. M. Roget, M.D., Sec. R.S7
The author commences his paper by stating that great interest attaches to the study of the ]\Iyriapoda, from the Edready known fact that their mode of developement, by an increa.5e in the number of segments, is directly the reverse of that of true insects in which the developement of the perfect individual is accompanied by an ap- parent diminution in the number of these parts. He remarks, that although the developement of the ]\Iyriapoda has already been ex- amined by several eminent naturalists, such as Degeer, Savi, Gervais, and Waga, some of the most important facts relating to it have, nevertheless, escaped their notice, and he proposes, therefore, to lay before the Society the result of his own investigations on this sub- ject, and also his examinarions of the organs of reproduction.
The paper is divided into four sections. In the first, the author describes the organs of reproduction, and shows that the part5 de- scribed by Treviranus, both in the male and female Julus, are only the efferential ducts in the male, and the oviduct in the female ; that in the former there are developed, from the sides of the efferen- tial ducts, a large number of sacs, the structure of which he de- scribes, and states his opinion that these are the proper secretory organs in the male, but remarks that be has not been able to follow out the organs to their fullest extent. In the fema-le, he shows that the oviduct described b}' Tre^-iranus is covered by an immense num- ber of o^dsacs, each secreting only a single ovum ; that many hun- dreds of these exist around the duct, a large proportion of which never reach maturit}^ being retarded in their growth by the deve- lopement of others immediately around them : and that the ova, when matured, are passed fi"om the ovisacs into the duct, -and are then all deposited at one time. He adverts especially to the remarkable condi- tion of the female oviduct being a single organ, throughout the greater part of its extent, but having a double outlet ; and shows its analogy in the internal portion of the organs to those of some in-
