720 PHYSIOLOGY IN BELATION TO 



The human anatomist who has once seen in the lower animals the 

 structures which represent, as it were, in exaggeration or caricature, 

 the human costocoracoid membrane; the tuberculum pubis, with 

 the homologue of the clavicle which is attached to it as Poupart's 

 ligament ; or the supracondyloid process of the humerus — is not 

 likely to forget their existence when, with either scalpel or bistoury 

 in hand, either for the ligature of an artery or the setting free of a 

 hernia, he has to deal with their representatives in the human 

 frame. But, if I am right in thinking that the ciliary muscle in 

 the eye would not have secured for itself the notice which it has 

 done of late years, had it not been for the much more obvious 

 manifestation of a similar, if not homologous, muscular apparatus 

 in the eye of a bird, I apprehend that I am justified in saying that 

 every surgeon who performs Mr. Hancock's operation of cylicotomy 

 for glaucoma is under obligations, whilst so doing, to Comparative 

 Anatomy and Sir Philip Crampton. I need not speak of the 

 bearing of the discovery of this muscle in the human eye by Mr. 

 Bowman upon the physiology of its adjustment to clear vision at 

 varying distances. Pure Physiology, again, unassisted by Com- 

 parative Anatomy, has made out much of pure function ; but, much 

 as has been attempted in the way of experiment with infusions of 

 pancreatic substance, and with the introduction of cannulae into the 

 duct of the gland, I am inclined to think that a comparison of the 

 relative size of the gland in the carnivora and the herbivora re- 

 spectively, in a dog, say, and in a rabbit, points as unmistakably as 

 any of the lines of experiment just referred to — which, by the very 

 nature of the case, are greatly beset with several sources of fallacy 

 — to the fact that this salivary gland is concerned as much with 

 the digestion of albumen and fat, as with that of starchy substances. 

 With the remark that Hyrtl's discovery (' Wien. Zool.-Bot. Ges.,' 

 1 86 1, cit. Henle, ' Handb. der Anat.' ii. 310) of the diverticular 

 character of the glomeruli in the kidney of the selachians and 

 amphibia bears not a little upon the existence of a similar arrange- 

 ment between the vasa recta and the renal arterioles in the human 

 kidney, whereby, as by the direct communication shown by Schroeder 

 van der Kolk to exist between the arteries and veins of the pia 

 mater, the capillary circulation may be skipped, and the tissues 

 in relation with it left at rest, I leave this part of my subject, and 

 begin the concluding portion of my addi'ess. 



