202 Scientific Intelligence. Anatomy and Physiology. 



ceased to grow. His intellectual development, on the other 

 hand, does not appear to have been arrested ; and his parents, 

 who accompany him, declare that he speaks with facility the 

 Italian, French, and German languages, besides the Illyrian, 

 and another dialect which are common on the shores of the 

 Adriatic. The members of the Medical Section of the Academy 

 were requested more particularly to examine him. 



ANATOMY AND PHYSIOLOGY. 



18. Researches on the Structure of the Teeth. Extract of a 

 letter from M. Retzms to M. Flour ens. Messrs Retzius and 

 Purkinje, have been engaged much about the same time, but 

 unknown to each other, in microscopic researches on the teeth. 

 The observations of the latter anatomist have been published in 

 the Inaugural Theses of two of his pupils, viz. those of Messrs 

 Frankel and Raschow ; and M. Retzius has published his in 

 the last volume of the Memoirs of the Academy of Stockholm, 

 which will speedily appear. M. Purkinje, says the author of 

 the letter, has carried farther than I have done his researches 

 upon the enamel ; and I believe that I on the other hand have 

 pushed my investigations further on the structure of the osseous 

 portion. The two preparations which I transmit along with 

 this letter, will enable you to verify the accuracy of my con- 

 clusions. Both M. Purkinje and myself have recognised that 

 the osseous substance is principally composed of waving fibres, 

 and of hollow cylindrical canals, which extend from the cavity 

 of the pulp or lining membrane in a radiating manner towards 

 the surface ; I have observed that they are ramified with great 

 regularity, and but rarely communicate with each other. Un- 

 der the microscope they appear like vessels which are filled 

 with a white substance. I may add that the same structure 

 is witnessed in the teeth of all the vertebrata. Since these ob- 

 servations were published, I find that Leuwenhoeck had made 

 similar ones, but they had entirely been lost sight of. The two 

 preparations I send you are prepared from human teeth, and 

 on both a groove may be found, the one running vertically, the 

 other horizontally, and in the centre of the crown. We have 

 both discovered the cortical substance of Tenon, which surrounds 

 the root of the human teeth. This substance, according to our 



