466 Eben Clayton Hill. 



.3 per cent, hydrochloric acid. These specimens in pnre glycerine 

 can be permanently kept cleansed of any small particles of un- 

 digested gland. They are not at all friable, and one perfect double 

 injection clearly defines the entire blood supply of the gland. Other 

 thick blocks of the testis were cleared without digestion in 1 per cent. 

 potassium hydroxide after hardening in 95 per cent, alcohol. These 

 specimens showed the capillary network around the lobules and 

 careful dissection revealed the lobular arrangement with its blood 

 supply. 



Water macerations similar to those used by Dr. MalF in studying 

 the structure of the spleen were attempted without success. This 

 was rather puzzling until investigations of the reticulum surround- 

 ing the lobules was begun. So dense and firm are the bands of 

 reticulum encasing these tubules that the entire gland will macerate 

 in water before any of the cells can be shaken out. Also the 

 trabeculae, which figure so conspicuously in all illustrations of the 

 human testis, disappeared under maceration. The causes of this 

 will be taken up in discussing the blood supply. 



In studying the reticular structure entering into the gland. Mall's 

 method^ used so successfully by Flint^ in his work on the adrenal 

 was followed. 



Arnold, in 1847, described the course of the spermatic artery 

 and its branches. His beautiful illustrations show quite accurately 

 and clearly the anterior and posterior scrotal arteries and the ex- 

 ternal and internal spermatic arteries. He traced the latter in the 

 cord where it gives off two or three branches to the epididymis, one 

 of which anastomoses with another small branch of the internal 

 spermatic artery which follows down the vas deferens. His dia- 

 gram and account show these branches to the gland proper passing 

 under the albuginea, but not penetrating the testis at the medias- 

 tinum. Arnold noted in his article the observations made by 



"Mall, F. P. The Structure of the Spleen. Johns Hop. Hosp. Rept. 



*Mall, F. P. Reticulated Tissue and Its Relation to the Connective Tissue 

 Fibres. Johns Hop. Hosp. Rept., Vol. 1. 



'Flint, J. M. The Blood "Vessels, Angiogeuesis, Organogenesis, Reticulum 

 and Histology of the Adrenal. Johns Hop. Hosp. Rept, Vol. 9. 



