114 Transactions of the Society. 



and physiology, all came within his ken, and to him, as modern 

 nomenclature indicates, we owe much of our early knowledge of 

 the structure of the skin, of the structure and functions of the 

 organs of taste, of the lungs, liver, spleen, and kidney, whilst on 

 his observations is founded our present knowledge of the developing 

 ovum. So pregnant were his researches on the structure and re- 

 lations of the capillary vessels, and on the lymphatic glands and 

 spleen, that of the first it has been said that " Harvey made their 

 existence a logical necessity ; Malpighi made it a histological cer- 

 tainty."* Whilst in connexion with the second — observations of 

 special interest to the pathologist — he described the enlarged lym- 

 phatic glands and the curious suet-like nodules in the spleen which 

 were afterwards more fully described by two great English physicians 

 of the nineteenth century, Hodgkin in 1832,t and later Samuel Wilks, 

 who, attaching to this disease the name of the earlier observer, termed 

 it Hodgkin's disease, lymphadenoma, or pseudo-leukaemia. By his 

 indefatigable researches, Malpighi staked a claim for the anatomist 

 in the field of histology, a claim that they cannot be asked to resign 

 unless good cause can be adduced why they should do so. That cause 

 now exists. For some time after the birth of physiology the Micro- 

 scope could play but little part in the elucidation of the problems' 

 with which the physiologist had to deal ; but, as the Microscope was 

 improved and histology was advanced almost to the dignity of a 

 separate branch of science, it soon became manifest that altered 

 function is invariably associated with altered structure, and that 

 it is possible to determine by careful histological examination 

 of secretory cells whether they were resting, or whether they were 

 functionally active at the time that their structures were "fixed." 

 Moreover, it may be determined whether such cells as those of the 

 brain were resting when fixed, were active after a period of rest, or 

 whether they were fixed at the end of a long or strenuous period 

 of activity. Accepting and verifying the observations of the 

 normal histologist and physiologist, the pathologist has, by means 

 of the Microscope, been able to trace the various stages of stimula- 

 tion by morbid irritants of the cells of tissues and organs, to 

 follow the processes by which these cells and tissues have become 

 more or less permanently modified, and to observe the changes 

 during their reversion to their original and normal condition ; or, 

 as they have gradually wasted or degenerated, until they reached 

 a stage at which not only are they useless to the individual but 

 are by their presence an actual menace. Living, they had a useful 

 function to perform ; dead, they are foreign bodies, which not 

 only cumber the ground, but may harbour enemies to the organism 

 that otherwise could find no foothold or coign of vantage from 

 which to attack it. 



* Fraser Harris, Nature, London, 1911, p. 584. 

 t Med. Chi. Trans. London, 1832, xvii, p. 68. 



