100 Malpighi and the Physiology [lect. 



" immense number of rounded particles, possessing the shape of 

 "as it were a fiat oval but nevertheless wholly regular. These 

 " particles seemed however to contain within themselves the 

 "humour of other particles. When they were looked at sideways 

 " they resembled transparent rods as it were and many other 

 " figures, according, no doubt, to the different ways in which 

 " they were rolled about in the serum of the blood. I remarked 

 " besides that the colour of the objects was the paler the more 

 " highly they were magnified by means of the microscope." 



After this we owe the first real accurate description of the 

 red corpuscles to Leeuwenhoek, who in 1674 in the Philosophical 

 Transactions gave an account of the red blood corpuscles in man, 

 and in various papers carefully described the blood corpuscles of 

 different animals, shewing that while circular in mammals they 

 are oval in birds, frogs and fishes, and proving that in all cases 

 the redness of blood is due to these red bodies. 



The discovery of the capillaries and the first observation of 

 red blood corpuscles were achievements of no mean value ; but 

 still more important perhaps than these were Malpighi's 

 labours, many and varied, on the structure of glands and 

 glandular organs. 



Before I go on to speak of these however I must say a 

 few words concerning two little tracts which he published in 

 1665 during the last year of his stay at Messina, one on the 

 tongue (De lingua exercitatio epistolica), addressed to Borelli, 

 the other on the external organ of sense (De externo tactus 

 organo exercitatio epistolica), addressed to his Sicilian patron 

 Ruffo. 



Fabricius had made known the distinction between dermis 

 and epidermis. The papillae of the tongue, being obvious 

 structures, had long of course been known ; but the general 

 opinion was that they were organs secreting fluid and so 

 helping to keep the mouth moist ; and the papillae of the 

 skin were wholly unknown. 



Malpighi, beginning to work on the tongue but extending 

 his researches to the skin, discovered that lower layer of the 

 epidermis, the rete mucosum, which we more frequently now 

 call after him the Malpighian layer. The fact that the surface 



