56 PR0CEEDTN08 OF THE 



heiui, among the Arachnida (Quart. Joum. Micros. Sci., July and 

 October 1881). The most important conclusion to which Prof. 

 Laukcster is led is, that the four pairs of lung-books of the Scor- 

 pion are the equivalent of the four hindmost pairs of gill-books of 

 the King-Crab, the most anterior of the five pairs of the King- 

 Crab's gill-books corresponding to the "pccten " of the Scorpion, 

 whilst the genital operculum in each animal corresponds both in 

 structure and position. 



Yertebeata. — In the great group of Vertebrates embrj-olo- 

 gi.sts have been active. AVe have not only Mr. Balfour's second, 

 volume of the ' Comparative Embryology,' but also a paper from 

 his pupil, Mr. Ileape, on the development of the Mole (T«Z^«) 

 (Proc. Eoy. Soc.) ; and an important memoir by the veteran eiu- 

 bryologist, Prof. Kolliker of AViirzburg, on the development of 

 the germ-layers of the Eabbit. Both these memoirs tend to show 

 that the development of the Mammal is a very strangely modified 

 one ; and that it cannot be brought under the general scheme of 

 development by formation of two primary layers (ectoderm and 

 endoderm) through invagination, as had been erroneously main- 

 tained by Edouard van Beneden of Liege. 



Dr. Bcrthold Hatschek, in a beautifully illustrated memoir, has 

 given an account of the develo])ment of Amj)liioxns, which is a 

 confirmation, and in some points a correction, of that of Kowa- 

 lewsky (Arbeiteu. "Wiener Anstalt. 1881). 



Professor Milues Mar.shall,of Manchester, has summarized the 

 results of his own and other recent observations on the develop- 

 ment of the cranial nerves and the primitive segments of the ver- 

 tebrate head in an essay published in the ' Journal of Anatomy,' 

 April 1882, which mai'ks an important step in knowledge. 



Amongst Fishes, the most important new work of the year has 

 been that of Professor F. M. Balfour on the development of the 

 paired fins of Elasmobranchs (Proc. Zool. Soc. 1881, p. 651), 

 showing that the paired fins are an anterior and posterior differ- 

 entiation of a once continuous lateral fin comparable to the con- 

 tinuous median dorsal fin. 



Amongst Aniphibia, we have Prof. Parker's studies on the 

 skulls of Anura (Phil. Trans., special volume) and on the skulls 

 of Urodela (Trans. Zool. Soc.) ; and Mr. Boulenger's Catalogue 

 of the Anura in the British Museum. 



Amongst Birds, the systematic treatises of Salvin and Grodman 

 on the fauna of Central America, and of Salvadori on the orni- 

 thology of the Moluccas, are important contributions. Not less 

 so the pala!ontological memoirs of O. C. Marsh on the characters 

 of ArchcEopteryx, and on Jurassic Birds and their allies, in the 

 ' Geolog. Magazine ' of 18S1. 



Pala?ontology furnishes the most important new matter in re- 

 ference both to Eeptiles and Mammalia. We have Marsh's 

 " Classification of Dinosauria " (Amer. Jouru. of Science, 1881), 

 and " Wings of Pterodactyles " in the same Journal. Cope, " On 



