ANNIVERSARY ADDRESS OF THE PRESIDENT. CIX 



trating by a plate the several forms obtained from the limestone- 

 fragments ; and by another plate, in a subsequent paper, several 

 British and Foreign species of the same genus. 



He has also published in the same periodical an interesting account 

 of some species of Leperditia^ another family of Palaeozoic bivalved 

 Entomostraca, larger than the BeyrichicRy and characteristically 

 distinct. They are also from the Silurian rocks of Scandinavia, 

 Russia, Arctic America, and England, except one from the Devonian 

 rocks of Normandy. After narrating the general facts of our know- 

 ledge of these minute entomostracan bivalves, peculiar to the palaeo- 

 zoic formations, Mr. Jones describes the principal forms of the genus, 

 comprising seven species, accompanied by two plates of illustra- 

 tions ; and, after some observations on the genus itself and its points 

 of resemblance with the more recent and the existing forms of Lim- 

 nadidse and Cypridininse, he observes that the study of this peculiar 

 group may be of use not only in showing the difficulty that exists 

 in coordinating the fossil genus specially referred to (so far as the 

 remains of the carapace will help us) with its known allies, but also 

 to some extent in illustrating another example " of the combination iu 

 extinct animals of characters which are separately manifest in exist- 

 ing species." 



The same publication also contains a notice by Dr. Thomas 

 Wright of a new genus of fossil Cidaridce, to which he has given 

 the name of Hemipedina. He observes that in his memoirs on 

 the Cidaridse of the Oolites, three species were described, of which 

 the true generic position seemed even then uncertain. The materials 

 then known did not justify the proposing of a separate genus for 

 their reception. The subsequent discovery of an interesting series of 

 new congeneric forms has now enabled him to rectify the determina- 

 tion and to propose the new genus Hemipedina for the group. 

 Sixteen species from different liassic and oolitic beds are described, 

 which, with the exception of four from France, are all English. 



Mr. Thomas Davidson has published some remarks on the Sy- 

 stematic arrangement of recent and fossil Brachiopoda, iu the 16th 

 volume of the ^ Annals of Natural History,' for the purpose of sub- 

 mitting a more perfect arrangement of classification than the one 

 published iu 1853. But even this classification Mr. Davidson ad- 

 mits must not be considered as finally correct. The paper contains 

 an improved table of the families and genera in the form in which it 

 will be published in the forthcoming foreign editions of the intro- 

 duction to his work on British fossil Brachiopoda, and also explains the 

 changes which have been proposed in the different genera and sub- 

 genera. The author also adds some remarks on certain interesting 

 observations published abroad, but which appear to have been over- 

 looked by British naturalists. 



Amongst the many paleeontological works by which the past year 

 has been distinguished, none are more deserving of notice than 

 the two additional numbers of the PalcEontographica published by 

 Dunker and Hermann v. Meyer. These are the third and com- 

 pleting fasciculus of the fourth volume, and the first of the fifth 



