THE CAT. 



[CHAP. vin. 



titions before mentioned. They converge and anastomose (tubes of 

 adjoining lobules anastomosing also) as they approach the medias- 

 tinum and epididymis till they are greatly reduced in number, when 

 they assume a comparatively straight course, and are called the 

 tubuU recti t or vasa recta. These traverse the mediastinum and 

 then form a network of tubes called the rete 

 vasciilosum, from which network other tubes, 

 called rasa efferentia, arise, and these enter the 

 globus major of the epididymis. 



The tubuli seminiferi are formed of connective 

 tissue lined with a basement membrane and 

 epithelium which is never ciliated but con- 

 sists of nucleated granular corpuscles and nu- 

 cleated cells, which transform themselves into 

 the male generative elements. 



The structure of the epididymis is much 

 more simple than that of the testis. It con- 

 sists of an enormously long convoluted tube, 

 into the proximal part of which the vasa 

 efferentia open. 



These vasa efferentia, however, which are 

 nearly straight at first, do not remain so, but 

 each becomes much convoluted as it approaches 

 the canal of the epididymis, so that they form 

 a series of small conical masses called coni 

 vasculosi, the apices of which are turned 

 towards the testis and towards the apices of 

 the conical lobuli of that gland. They all 

 successively open into the canal of the epidi- 

 dymis. This canal has its convolutions sup- 

 ported by connective tissue (thus forming lobes). 

 It increases in size towards the end of the globus 

 minor, where it acquires thicker coats and 

 becomes the vas deferens. The vasa efferentia 

 are lined with ciliated epithelium, as is also 

 the case with the canal of the epididymis. 

 Sometimes a small tube, called a vas aberratis, 

 is given off from the commencement of the vas deferens. A very 

 small pedunculated structure in the vicinity of the head of the 

 epididymis is called the hydatid of Morgag-ni. A few convoluted 

 tubules (also near the head of the epididymis) are sometimes spoken 

 of as the Organ of Giraldes or par epididymis. These parts are quite 

 functionless remnants of a foetal structure which will be noticed 

 in the chapter on Development. 



The vas deferens the continuation of the canal of the epididymis 

 is at first much convoluted, but becoming straight extends up the 

 inner side of the epididymis, and thence upwards beside the spermatic 

 artery which goes to the testis, and the spermatic veins which leave 

 it, these vessels, with the vas deferens and the tissues which unite 



Fig. 11(3. DIAGRAM 



SHOWING THE ARRANGE- 

 MENT OF THE TUBES IN A 



MAMMALIAN TESTIS. 



a. Tubuli seminiferi, 

 coiled up in the se- 

 parate lobules. 



5. Vasa recta. 



c. Rete vasculosum. 



<?. Vasaefferentia,ending 

 in the coni vascu- 

 losi. 



I, e, g. Convoluted canal 

 of the epididymis. 



7t. Vas deferens. 



/. Section of the back 

 part of the tunica 

 albuginea. 



i, i. Fibrous processes 

 running between the 

 lobes. 

 ftos. Mediastinum. In 



the cat the mediastinum 



is not on one side, as 



in the above figure, but 



is nearly in the middle 



of the testis. 



