1877.] 



Mr. W. Shanks on 487^=486. 



551 



a dense plexus of valved vessels on the anterior surface of the abdominal 

 wall, corresponding to that on the pleural surface of the diaphragm. 



Upon the lymphatics of muscle they find the peculiar serous cells first 

 described by Ludwig and Schweigger Seidel, whose views they fully 

 confirm, in opposition to those expressed by Eanvier. They deny the 

 existence of stomata in the Mammalia, but admit it in the case of frogs ; 

 and as the peritoneum of the latter is lined by crenated lymphatic 

 endothelium, they admit its connexion with the lymphatic system ; but, on 

 account of the absence of the latter endothelium as well as stomata 

 from the serous cavities of mammals, they deny any connexion between 

 these and the lymphatics. While describing the structure of basement 

 membrane, they discuss the facts adduced by EHein and Debove as bearing 

 on the question of absorption, and give their own views on this question. 

 They hold that the lower surface of the diaphragm is an exuding one, 

 and only an absorbent one when all the natural conditions are reversed. 



They describe the minute anatomy of the lymphatics of the intestine, 

 and show that it is the glandular structures, and not the muscles of the 

 wall, that regulate the amount of these vessels. They also trace com- 

 plete identity between these and the lymphatics of striated muscle. In 

 either case they figure the connective-tissue cavities as forming the 

 radicles of the lymphatics, but hold that these are not the only lymphatic 

 afferents, nor that that is their only function. To prove this, they 

 discuss the nature of these cavities, as they have discovered them in 

 tendon and other gelatinous structures in different classes of animals to 

 be of the same structure as in the cornea. Unlike man, the small mammals 

 have no special vascular or lymphatic vessels in the peritoneal tissue, 

 being dependent on the muscles below for those structures. 



The authors finish by entering upon a minute description of the 

 technique employed by them, and offer a series of about 60 camera-lucida 

 drawings of preparations in their possession in illustration of their 

 researches. 



III. Remarks chiefly on 4872 = 486/' By William Shanks. 

 Communicated by the Rev. Gr. Salmon, D.D._, F.R.S. Re- 

 ceived November 29, 1876. 



In the cases of 3, 3^ = 1, also of 487, 487^ = 486, we are unable to show 

 why the Period itself is, in each case, divisible by the Prime. But we 



can show, with little labour, that the period arising from is itself 

 divisible by 487, and therefore that ^i=2 = 486. 



The num.ber composed of 486 9s is divisible by 487. Now this number 



