3568 Imperial Academy Naturae Curiosorum. 



reus, V. stellatus, and Sphaerosira Volvox of Ehrenberg ; these he believed to be all 

 different forms of the same organism. He called attention to the structure of these 

 objects, and more especially as regarded some points alluded to by Prof. Williamson, 

 in a paper recently published by that gentleman on that subject; and while in some 

 respects he expressed a different opinion from Mr. Willamsou, he fully agreed with 

 him that they were truly of vegetable origin, and not animals. This he considered as 

 proved both by their structure and their chemical composition. Thus, on testing their 

 tissues with iodine and sulphuric acid, he had discovered in them both cellulose and 

 starch. The analogies of their development with that of Protococcus nivalis and of 

 P. viridis, were very strong, as well as with the supposed animalcule called Euglenia 

 viridis. The author expressed his belief that the whole of the Monadinae, the Cryp- 

 tomonadinae, and the Volvocinia of Ehrenberg, belonged to the vegetable rather than 

 to the animal kingdom. 



A second paper, by Mr. Mummery, of Dover, " On the Development of the Young 

 in Tubularia indivisa," was read. The author, taking advantage of his residence on 

 the sea-shore, where these zoophytes abound, had for a considerable period attentively 

 watched the development of the ova, and the results of his observations form the sub- 

 ject of the present paper. The various changes in the ovum, from its first develop- 

 ment to its arrival at perfection, were minutely described. When the creature is libe- 

 rated, its future basal end appears first. It emerges slowly, withdrawing its tentacles 

 in succession until it sets itself at liberty. In this state it is not fixed, but free, and 

 may be seen crawling slowly upon the bottom of the vessel containing it, and elevat- 

 ing itself on the extremities of its eight tentacles. After a period of time varying from 

 one to four days, the animal which, in its free condition, has never been remarkable 

 for activity, having selected a suitable stone or the surface of some old polypidom, re- 

 verses its position, and attaches itself with the mouth upwards by the opposite extre- 

 mity, soon increases in size, and attains its usual form and characters, never removing 

 from its place after having once rooted itself. — J. W. 



Two Hundredth Anniversary of the Imperial Academy. — Simultaneously with the 

 meetings of the German Association for the Advancement of Science, the Imperial J 

 Academy Naturae Curiosorum, the oldest Natural-History Society in the world, has 

 resolved to celebrate its two hundredth anniversary. The following is the official in- 

 vitation : — 



" Breslau, July 24, 1852. 



" We have the honour of informing the Members and friends of the Imperial 

 Academy Naturae Curiosorum, in Great Britain, that the celebration of the two hun- 

 dredth Anniversary of our Society, which was postponed on account of the cold season 

 (the 1st of January being the real birth-day), will take place at Wiesbaden, on the 18th 

 of September, 1852, simultaneously with the meetings of the German Association for 

 the Advancement of Science. And it is to be hoped that the attendance will be most 

 numerous on that important occasion ; when every exertion will be made to render 

 the stay of the members and visitors as agreeable as possible. — The Presidium.'' 



