244 



THE CAT. 



[chap. VIII. 



titions tefore 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 

 tnbuH recti, or rasa recta. These traverse the mediastinum and 



then form a network of tubes called the refe 

 vasciilosum, from which network other tubes, 

 called rasa efferentia, arise, and these enter the 

 globus major of the epididymis. 



The tubuli seminifcri 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 jrenerative elements. 



The structure of tJie epidkhjnm 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 

 ejEferentia 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 

 rascu/osi, 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 ras 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 ras aberraiis, 

 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 3for(/af/)ii. A few convoluted 

 tubules (also near the head of the epididymis) are sometimes si)okeh 

 of as the Orejan of Girahtes or 2>arej)i(ti(/f/niis. These parts are quite 

 f'unctionlcss remnants of a foetal structure which will be noticed 

 in the chapter on Development. 



The vas deferens — the continuation of tlie 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, -wath-the vas deferens and the tissues which unite 



Fig. 111). — DiAliRA.M 



showing the arrande- 

 mext of the tubes in a 

 ^Iammalian Testis. 



ca. Tubuli seiiiiuifcvi, 

 coiled up in the se- 

 parate lobules. 



/). Vasa recta. 



r. Rete vasculosiiiii. 



('. VasaeflereHtia,eiKliiig 

 in the eoni vaseu- 

 losi. 



/, (', (/. Convoluted caual 

 of the epididyiuis. 



/'. Vas deferens. 



/. Section of the back 

 l)art of the tunica 

 alliuginea. 



i, i. Fibrous processes 

 running; between the 

 lobes, 

 /tos. Mediastinum. In 



the cat the niediastiiunn 



is not on one si<le, as 



in the above figure, but 



is nearly in the middle 



of the testis. 



