1870.] Meteorology. 275 



palaeontologists, a difference in horizon is sufficient to constitute a 

 difference in species ; hence the zones of Ammonites, each marked 

 by a different species, which is said never to occur above or below 

 a certain narrow bed or horizon. 



Professor Huxley would like to see the rise of a new race of 

 palaeontologists, relying simply on zoological characteristics, and not 

 upon geological position. A considerable reduction in the number 

 of species would, he thinks, undoubtedly result. 



Although the term species is too often used where variety would 

 be more appropriate, yet these distinctions — when kept within due 

 bounds — have been found of great value in tracing out, by their 

 characteristic fossils, the horizon of beds over widely-extended areas. 



Mr. Searles V. Wood, jun., continues his researches on the 

 Boulder-drift. He finds the Yorkshire Glacial clays are of two 

 kinds; the lower containing chalk-debris abundantly, the upper 

 containing chalk sparingly in its lower part, and gradually losing 

 it upwards. The Boulders of Shap Fell Granite only occur in the 

 Boulder-clay, without chalk. Mr. Wood ascribes their dispersion 

 to the agency of floating ice during the submergence of the district. 



The great chalky clay derived its chalk from the extrusion of a 

 great sheet of land-ice over the sea, the chalk-mud being due to the 

 abrading action of the ice. 



The anniversary of the Geological Society of London was held 

 on the 18th February, when the President announced that the 

 Wollaston Gold Medal had been awarded to M. Deshayes, as an 

 expression of the estimation in which his services to Palaeontology 

 and Geology (especially in regard to the classification of the Tertiary 

 formation and its Molluscan fauna) are held by geologists of this 

 country. 



The balance of the Wollaston Donation-fund was presented to 

 M. Marie Eouault, of the Geological Museum of Kennes, in aid of 

 his researches upon the palaeontology of the Devonian and Silurian 

 rocks of Brittany. 



Neither of the gentlemen was present, but both sent letters of 

 thanks. 



8. METEOEOLOGY. 



The subject which has secured to itself the most important papers 

 published lately has been the wind-systems of the globe, a question 

 which had been left at comparative rest for some time. 



Mr. Buchan's paper " On the Mean Pressure of the Atmosphere, 

 and the prevailing Winds over the Globe," appears in vol. xxv. of 

 the ' Transactions of the Eoyal Society of Edinburgh,' and has been 

 most carefully worked out. The mean monthly conditions of atmo- 



