A YORKSHIRE NATURALIST 105 



Amongst other points with which he had enriched 

 this edition were some extended notes on the struc- 

 ture and development of bones. The publication by 

 the Sydenham Society of an English translation of 

 the two works of Schwann and Schleiden on the cell 

 question had brought that subject prominently before 

 British physiologists. It had long been known that 

 certain minute cavities called lacunce were abundant 

 in most, or rather as was believed then to be the case 

 in all bones ; and the question which arose was Did 

 these lacunae originate in cells ? In 1 842, 1 amused 

 myself during my vacant hours in making some thin 

 sections of the bones of quadrupeds, with a view to 

 throwing light on the debated problem. These early 

 investigations led to others in 1848-50, which will 

 be noticed further on, when I shall have to call 

 attention to the importance of the two works just 

 named. 



A little later, my friend Mr. Sidebotham and I 

 were stimulated by the researches of Mr. Ralfs of 

 Penzance, to study practically the lower Confervacese, 

 the Desmideae, and the Diatomaceae. Spending one 

 evening together over these studies, my friend 

 showed me a small slide which he had received from 

 Mr. Reckitt of Boston, containing some beautiful 

 diatoms in a marine sediment from the Levant. 

 Examining these slides in search of diatoms, my eye 

 fell upon an object which made me spring out of my 

 chair. It was a perfect specimen of a marine For- 

 aminifer, the shell of which was perforated by 



