171 



LESSON XXXIV. 



STRUCTURE OF THE URETER, BLADDER, AND MALE 

 GENERATIVE ORGANS. 



1. SECTION across the ureter. 



2. Section of the urinary bladder vertical to the surface. 



In the sections of the ureter and of the urinary bladder, notice the 

 transitional epithelium resting on a mucous membrane, which is composed 

 chiefly of areolar tissue without glands, and the muscular coat outside this. 

 In the ureter there is some fibrous tissue outside the muscular coat, and at 

 the upper part of the bladder there is a layer of serous membrane covering 

 the muscular tissue. Sketch a section of the ureter under a low power, and 

 the epithelium of the bladder under the high power. 



3. Section across the penis. The blood-vessels of the organ should have been 

 injected so as the better to exhibit the arrangement of the venous spaces which 

 constitute the erectile tissue. Notice the large venous sinuses of the corpora 

 cavernosa and the smaller spaces of the corpus spongiosum, in the middle of 

 which is seen the tube. of the urethra. 



4. Section across the testis and epididymis. The sections are best made 

 from a rat's testis which has been hardened in alcohol and pieces of which 

 have been stained in bulk in dilute logwood. In these sections notice the 

 strong capsule surrounding the gland, the substance of which consists of 

 tubules which are variously cut, and the epithelium in which is in different 

 conditions of development 'in the different tubules. Observe the strands of 

 polyhedral interstitial cells lying in the loose tissue between the tubules and the 

 lymphatic clefts in that tissue. Notice also in sections through the epididymis 

 the ciliated epithelium of that tube. 



Sketch carefully under a high power the contents of some of the semini- 

 ferous tubules so as to illustrate the mode of formation of the spermatozoa. 



5. Examination of spermatozoa. The spermatozoa are to be obtained 

 fresh from the testis or seminal vesicles of a recently killed animal and ex- 

 amined in saline solution. Their movements may be studied on the warm 

 stage; to display their structure a very high power of the microscope is 

 necessary. Measure and sketch three or four spermatozoa. 



The ureter is a muscular tube lined by mucous membrane. The 

 muscular coat consists of three layers of plain muscular tissue, an 

 outer and inner longitudinal and a middle circular. Outside the mus- 

 cular coat is a layer of fibrous tissue in which the blood-vessels and 

 nerves ramify before entering the muscular layer. 



The mucous membrane is composed of areolar tissue and is lined 

 by transitional epithelium. 



