338 OSWALD S. LOWSLEY 



In one specimen there was observed a growth of branches from 

 lateral lobe tubules into the region usually occupied by the middle 

 lobe, the latter structure in this case being absent. 



In the prostate of the new-born near the apex the lateral lobes 

 have two extensively branching tubules which extend up into 

 the anterior commissure and practically form a glandular commis- 

 sure in this region. 



The lateral lobes are in most cases very well separated from 

 each other anteriorly a considerable area of stroma being present, 

 in which are found the anterior lobe tubules. Mesially the ejacu- 

 latory ducts, urethra and middle lobe are interposed and there is 

 a definite plane of connective tissue which sharply separates their 

 posterior branches from the posterior lobe. 



The number of tubules forming the two lateral lobes vary from 

 twenty-seven to forty-six, the average number being thirty-seven. 



The posterior lobe is made up of tubules which begin to develop 

 with the other prostatic tubules at the third month. They are 

 found on the floor of the urethra below the openings of the ejacu- 

 latory ducts and their direction of growth is behind those struc- 

 tures back towards the bladder. They compose the main mass 

 of the apex of the gland and the posterior lobe is that part of the 

 gland which is palpated per rectum. Just anterior to this lobe is 

 found in the older stages a stroma of connective tissue free from 

 tubules which separates it from the posterior parts of the lateral 

 lobes and from the ejaculatory ducts. The tubules of this part 

 of the prostate send a few branches forward in the region of the 

 apex as do the most anteriorly arranged branches of the lateral 

 lobes. They are quite large with numerous branches but are not 

 very numerous, the smallest -number being four, the greatest 

 eleven, and the average in six specimens is eight. 



This lobe is present in all fetuses here studied and in the new- 

 born. It is an independent structure developing from tubules 

 which are separated from those composing the other lobes and 

 being divided from them by a definite capsule which is laterally 

 connected with the capsule of the gland. 



The posterior lobe is of considerable importance for several 

 reasons. In doing Young's operation for perineal prostatectomy 



