THE PRESIDENT'S ADDRESS. 379 



anatomy of insects. It is undoubtedly G. Newport's article 

 " Insecta," in Todd's " Cyclopaedia of Anatomy and Physiology," 

 published in 1836-9. 



Newport was not a mere compiler of the work of others ; he was 

 a careful and painstaking anatomist, and where he differs from his 

 predecessors, so far as I am a judge, he was almost invariably 

 right. Every student should carefully peruse this article. Amongst 

 more modern works on insect anatomy I may mention my own work 

 on the blowfly, written, I may say, prematurely, when I was young, 

 published in 1870 ; Dr. Karl Kraspelin's admirable paper on the 

 proboscis of the same insect, published in Kolliker's " Zeitschrift " 

 in 1883, by far the most complete and accurate description yet pub- 

 lished on a subject which has an enormous literature ; and, lastly, 

 Messrs. Miall and Denny's work on the cockroach, published in 

 1886, a work which is professedly elementary, but, as far as it goes, 

 eminently satisfactory and necessary to every student who wishes 

 to undertake entomotomy. 



So far I have confined my attention to works on the subject of 

 insect anatomy which are either general or are monographs on 

 some special insect. Let us now take a glance at the advances 

 which have been made with regard to the anatomy of the sensory 

 and nervous structures and the physiology of insects. 



This branch of our subject took its origin more especially from 

 the researches of Johannes Miiller, who published a work on the 

 comparative physiology of vision (" Zur Vergleichenden Physio- 

 logic des Gesichtssinnes) in 1826, a work which has now become 

 classical. We must remember that Miiller had very indifferent 

 means of research at his disposal. Microscopes in 1826 were ill 

 adapted for difficult problems, and the modes of preparing objects 

 for observation were nearly as primitive as in the days of Swam- 

 merdam. With all its faults and optical impossibilities, Miiller's 

 theory of the manner in which the compound eye subserves its 

 function, although repeatedly attacked, has even at the present day 

 a strong hold on many minds. 



Gottsche in 1852 first seriously attacked Miiller's theory, and 

 showed the subcorneal images. Although these were known to 

 Leeuwenhoek, attention had not been drawn to them in relation to 

 Miiller's theory of " Mosaic vision." 



Since that date the compound eye has been a battle-field with 

 entomotomists. Claparede gave the first fairly complete descrip- 



