Notices of New Books. 4875 



• On the Heart and Circulation in the Pycnogonidae.' By Dr. A. 

 Krohn. [Extracted from Weigmann's Archiv for 1855, p. 6.] 



'Abstract of a Monograph of the Family Gorgonidae.' By M. 

 Valenciennes. 



' On the Genus Assiminia.' By Dr. J. E. Gray, F.R.S., V.P.Z.S. 



' On the Law which has regulated the Introduction of New Species.' 

 By Alfred R. Wallace, F.R.G.S. 



* On some New Species of Hemipedina from the Oolites.' By 

 Thomas Wright, M.D., F.R.S.E. 



c Short Biographical Notice of the late Dr. Johnston, of Berwick- 

 upon-Tweed. 



Bibliographical Notice : — ; The British Flora, comprising the Phae- 

 nogamous or Flowering Plants, and the Ferns.' The 7th edition, with 

 additions and corrections. By Sir William Jackson Hooker, K.H., 

 D.C.L., &c, and George A. Walker Arnott, LL.D., &c. 



Proceedings of Societies : — Royal, Linnaean, Botanical of Edin- 

 burgh, Zoological. 



Miscellaneous: — Monstrosity of Antirrhinum majus; by Dr. J. E. 

 Gray. Notice on the Horns and Skull of the Arnee ; by Dr. J. E. Gray. 



In the Proceedings of the Royal Society occurs the report of a paper 

 by Dr. John Davey, intituled * Some Observations on the Ova of the 

 Salmon in relation to the Distribution of Species.' In this the Doctor 

 gives the result of experiments on ova submitted to various tests, with 

 a view to elucidate the geographical distribution of fishes. The con- 

 clusions drawn from the observations are as follows : — 



" 1. That the ova of the salmon in their advanced stage can be ex- 

 posed only for a short time to the air if dry, at ordinary temperatures, 

 without loss of life ; but for a considerable time, if the temperature be 

 low, and if the air be moist; the limit in the former case not having 

 exceeded an hour, while in the latter it has exceeded many hours. 



" 2. That the vitality of the ova was as well preserved in air saturated 

 with moisture as it would have been had they been in water. 



" 3. That the ova may be included in ice without loss of vitality, 

 provided the temperature is not so low as to freeze them. 



" 4. That the ova, and also the fry recently produced, can bear for 

 some time a temperature of about 80° or 82° in water, without materially 

 suffering ; but not without loss of life, if raised above 84° or 85°. 



" 5. That the ova and young fry are speedily killed by a solution of 

 common salt nearly of the specific gravity of sea-water, viz. 1026 ; and 

 also by a weaker solution of specific gravity 1016. 



" Finally, in reference to the inquiry regarding the distribution of 



