Royal Society. 249 



bibliographic references and statements of habitat, and under each 

 genus references to the published descriptions, if any are in exist- 

 ence, of the transformations of the species. 



From the careful manner in which it has been prepared, this work 

 cannot but be of the greatest service to future students of the Phyto- 

 phaga, more especially if the author be enabled, as we trust he may, 

 to finish the remaining (and far more difficult) portion of his task in 

 the same style. 



The Appendix consists of descriptions of new species (cited in 

 their proper places in the catalogue) by the author and Mr. H. W. 

 Bates, the latter describing those Amazonian species which were col- 

 lected by himself. These descriptions are very numerous. 



PROCEEDINGS OF LEARNED SOCIETIES. 



ROYAL SOCIETY. 



June 21, 1866. — Lieut.- General Sabine, President, in the Chair. 



"Observations on the Ovum of Osseous Fishes." By W. H. 

 Ransom, M.D. 



In this paper the author has communicated the details of ob- 

 servations of which the principal results were stated in a short paper 

 published in the Proceedings of the Royal Society in 1854, and of 

 further researches on the structure and properties of the egg in 

 several species of osseous fishes. The methods employed in deter- 

 mining the functions of the micropyle, and in conducting the various 

 inquiries entered upon, are described. The development of the ova- 

 rian ovum is traced in two species of Gasterosteus ; and the yelk-sac 

 is shown to increase by interstitial growth, and not by apposition 

 of layers on either surface. A minute description of the germinal 

 vesicle and its contents is given ; and the germinal spots are shown to 

 be drops of a thick fluid substance so apt to change their normally 

 round form and to vacuolate in their interior, that no perfectly in- 

 different medium was found in which to examine them. The pri- 

 mitive yelk first formed around the germinal vesicle is shown to 

 differ in some of its chemical and physical properties from that of 

 the ripe ovum ; it is solid, and does not consist of two distinguishable 

 portions. On its surface a yelk-sac was found in very early ova, but 

 in the smallest eggs examined it could not be separated. 



The reactions of a variety of albumen allied to myosin, which the 

 author has found in variable proportions in the yelk of all the fishes, 

 amphibia, and birds which he has examined, are described, the yelk 

 of the salmon being selected for experiment. This substance, to 

 which the name albumen C is given provisionally, is remarkable, in 

 addition to its being easily precipitable by water in excess, for form- 

 ing under certain conditions a solution in dilute nitric acid not 

 coagulable by boiling. 



Some account is rendered of the reactions of au acid compound of 



