1881.] Dr. Watney. Minute Anatomy of the Thymus. 11 



IV. "Further Note on the Minute Anatomy of the Thymus." 

 By Hekbert Watney, M.A., M.D. Cantab. Communicated 

 by E. A. Schafer, F.R.S. Received August 26, 1881. 



Ciliated epithelial cells are found in the thymus of the dog : this is 

 not the case in quite young animals, but ciliated epithelium can 

 always be demonstrated in the thymus of a dog over thirty months 

 old, and often in those of much younger animals. In the older dogs 

 the ciliated cells are found lining cysts, and the cysts appear to 

 increase in size with the age of the animal. The ciliated epithelial 

 cells take origin from connective tissue corpuscles. The connective 

 tissue corpuscles forming the network in the medullary portion are in 

 places massed together, forming concentric corpuscles of small size ; 

 in these masses small cavities are formed, and the lining cells are trans- 

 formed into ciliated cells. 



In the thymus of the tortoise small cavities are found lined by 

 columnar epithelium. The epithelial cells arise from connective tissue 

 corpuscles, the process being essentially the same as that just described 

 in the dog. 



The fluid in the lymphatic vessels leading from the thymus can be 

 obtained by tying the vessels immediately after death. The lymph 

 thus obtained contains considerably more colourless corpuscles than 

 the lymph of the large lymphatic vessels of the neck. The blood in 

 the veins passing from the thymus does not appear to differ from the 

 blood of the jugular vein. 



V. " Experimental Researches on the Propagation of Heat by 

 Conduction in Bone, Brain- tissue, and Skin." By J. S. 

 Lombard, M.D., formerly Assistant Professor of Physiology 

 in Harvard University. Communicated by Dr. Brown- 

 Sequard, F.R.S. Received October 1, 1881. 



(Abstract.) 



The experiments (over 900 in number) were made on the skull and 

 long bones of sheep, the ribs of oxen, and on the brain and skin of 

 sheep. Thermo-electric apparatus was employed in the work. 



The different tissues were thus prepared : — In the case of bone, a fresh 

 piece was ground smooth on one side, and the face of the thermopile 

 accurately fitted to it ; then a thin coating of shellac varnish was 

 applied to the surface of the bone and to the face of the pile, and firm 

 pressure was maintained until the varnish was dry and permanent 



