SEVENTEENTH AND EIGHTEENTH CENTURIES l6l 



moved to contract. The nerves, which are hollow, form the passages out- 

 wards for this fluid, the nature of which Malpighi does not further describe, 

 although, like Willis, he seems to regard it mostly as some kind of fugitive 

 liquid. For the rest, he has made contributions to the knowledge of the 

 blood-vessels' ramifications in the brain; on the other hand, his speculations 

 in regard to the function of the cerebral cortex are not very enlightening, 

 just as, on the whole, Malpighi was more of a practical observer than a 

 theoretician. It was left to Swedenborg, a couple of generations after Mal- 

 pighi, to work out an explanation — partly based on the latter's observa- 

 tions — of the localizations in the cortex of the brain, which even our own 

 age might well think remarkable. — Finally, Malpighi studied the kidney 

 and the spleen, using the same methods as those applied to his observations 

 of the above-mentioned organs, and in this field, too, he achieved valuable 

 results; in the kidney he established the course of the blood-vessels and of 

 the tubules and has in general given a good description of the inner structure 

 of the organ in man and in several other mammal forms; the glomeruli of 

 the kidney still bear his name, and likewise the name of the Malpighian 

 follicular bodies in the spleen testify to his powers of observation. Extremely 

 useful has been Malpighi's monograph on the tongue, the muscles and nerves 

 of which he explained and the papillas of which he described and charac- 

 terized as gustatory organs. And finally he published an account of the de- 

 velopment of the hen's egg, which forms a creditable supplement to the 

 investigations previously carried out by Fabrizio and Harvey. In the sphere 

 of invertebrate biology Malpighi has also performed a service by investi- 

 gating the structure and history of the development of the silk-worm; he 

 discovered in this subject the excretal organs characteristic of the Tracheata, 

 which are now called the Malpighian tubes, and in other respects, too, he 

 laid the foundations of our knowledge of the anatomy of insect larval forms 

 and likewise made valuable observations regarding the butterfly's evolution 

 out of the pupa and its anatomical structure. 



Malpighi's works on vegetable anatomy 

 There still remains to give an account of Malpighi's activities as a pioneer 

 in a quite new field — vegetable anatomy. Biology, as a universal science 

 of life and its manifestations, has for obvious reasons been based principally 

 on the study of those creatures which have stood in the closest relation to 

 man — that is to say, first and foremost man himself, and secondly the higher 

 and lower animals; for the purposes of this science plants have as a rule come 

 last. There are two fields of biological study, however, in which plants have 

 from the beginning been more useful for standardizing purposes than ani- 

 mals — namely, classification and the cell and tissue principle. The fact that 

 plants have proved a more convenient starting-point in this latter sphere 

 is, of course, due to their having, on account of their cellulose formations. 



