196 Presentation of the Hoyal Society Medals. 



would thus be complete in evei'y direction, without the dark 

 intervals produced by reflectors of double curvature, which 

 only emit one large parallel beam. 



It is, however, to be remembered that, when it is required 

 to carry a parallel beam of light only in a single direction, 

 and to a great distance, this species of reflector and lamp can 

 be of no service, its use being to carry forwai'd a powerful 

 light over a horizontal angle of considerable extent. 



Presentation of the Boyal Society Medals to Dr M. Barry arid 

 Mr Ivory, and the Copley Medal to Mr Brotvn. By the Pre- 

 sident, Lord Northampton. 



I have"*the honour, Gentlemen, to inform you that the Coun- 

 cil of the Royal Society have, by an unanimous decision, 

 awarded the Royal Medals to Dr Martin Barry and Mr Ivory, 

 and the Copley Medal for the year to Mr Robert Brown ; 

 and I shall now beg leave to address myself to those three 

 Gentlemen. 



Dr Bai-ry — It giA^es me sincere pleasure to bestow this me- 

 dal on a gentleman who has so well deserved it, by researches 

 in a diflicult and important portion of animal physiology.* 

 Your merits have been appreciated by men much more capa- 



* These researches are the subject of Dr Martin Barry's papers " On 

 Embryology-," commvmicated to the Royal Society in 1838 and 1839. 



In these memoirs the author has brought to light many new and interest- 

 ing facts, and has repeated and confii'med previous obser%-ations regarding the 

 nature, formation, and development of the ovum in the vertebrata, and espe- 

 cially in the mammalia. 



The importance of the subject and the difficulty of its investigation, render 

 the establishment of facts previously kno^vn extremely acceptable to physio- 

 logists. ■ But the novel matter contained in Dr BaiTy's Memoirs forms a 

 considerable proportion of them. Without entering into unnecessary detail , 

 we may mention that the author has determined the order of formation of the 

 different parts of the ovum, and the nature and mode of development of the 

 vesicle (ovisac), in which thes? processes take place. He has, in like man- 

 ner, discovered the nature and traced the development of the so-called disc of 

 M. Baer, and has detected in it the mechanism which mainly regulates the 

 transit of the ovum into the Fallopian tube. The second series of Dr Barry's 

 obsen'ations maltes Ivnowu the changes which the ovum undergoes in its 



