TESTICLE (NORMAL ANATOMY). 



thelial cells. There is no appearance of an 

 intertubiilar substance ; the ducts are merely 

 connected by a loose network of vessels, and 

 consequently readily admit of being sepa- 

 rated and unravelled. The tubes, when suc- 

 cessfully injected with quicksilver, form a 

 beautiful anatomical preparation. Sir A. 

 Cooper succeeded in filling the tubes with size 

 injection ; but he has not described the mode 

 in which it was effected, and other anatomists 

 have failed in similar attempts.* 



When the tubuli seminiferi are unravelled, 

 they are found to divide and form numerous 

 anastamoses, which increase in frequency to- 

 wards the circumference of the testicle. "(See 

 diagram, /g. 633. a 1 a 1 ). The tubuli thus form 

 one vast network of communication, so that it 

 is impossible to isolate completely either a duct 

 or a lobule. The credit of making this interest- 

 ing discovery of the anastamoses of the se- 

 minal tubes is due to Lauth. In only one 

 instance did he succeed in finding a duct, ter- 

 minating in a blind pouch, and this he regarded 

 as exceptional. Blind ends have been found, 

 however, more frequently by Krause. The 

 anastamoses of the tubules have been observed 

 in the rat and other animals as well as in man. 

 The convolutions of the seminal tubes di- 

 minish in number as they approach the me- 

 diastinum, and cease altogether at a distance 

 of from one to two lines, where two or more 

 unite to form a single straight duct, termed 

 vas rectum, which joins the rete testis at a 

 right angle (a~ a"). The vasa recta are very 

 slender, and easily give way when injected : 

 their calibre, which is greater than that of the 

 seminal tubes, is estimated by Lauth at y^th 



Fig. 633. 



Diagram of the testicle. (After Lauth.') 



a a a, tubuli; a 1 a 1 , subdivisions and anastamoses 

 of the tubuli ; a" 2 a 1 *, vasa recta. 

 The other references are the same as in fig. C32. 



*_Sir A. Cooper's beautiful preparations of the 

 testicle are preserved in the Museum of the Royal 

 College of Surgeons of England. 



979 



of an inch. Haller reckoned their number at 

 twenty, which is, however, too few. 



Rcte Testis, as its name implies, consists of 

 a plexus of seminal tubes, which occupies the 

 corpus Highmori, or mediastinum testis. The 

 vasa recta, after penetrating the walls of this 

 body, terminate in from seven to thirteen ves- 

 sels which, running parallel to each other in 

 a waving course, and frequently dividing and 

 anastomosing, form the rete testis. (b). Lauth 

 found the mean diameter of the vessels of the 

 rete in injected preparations ^ of an inch. 

 According to Prochaska, these vessels are 

 supplied with valves, but such is not the case. 

 Small dilatations, however, are often found in 

 different parts of the plexus. 



III. The Excretory Parts. The epididymis, 

 a continuation of the testicle, is a body of a 

 crescentic form, divided into an anterior and 

 upper extremity, called head, or gtobus major, 

 which is firmly attached to the testicle ; a 

 middle part or body, which is less in size, and 

 separated from the gland by a pouch of the 

 tunica vaginalis ; and a tail or globus minor, 

 connected to the testicle by areolar tissue. 

 The volume and weight of the epididymis 

 vary in different subjects, but are proportionate 

 to the size of the testicle. It is longer than 

 the testicle, measuring about two inches in 

 length and four or five lines in width. Its 

 name (from eVl upon, and 5i5v/j.os testis,) indi- 

 cates its position, which is along the postero- 

 superior border of the gland. The epiclidv- 

 mis is chiefly made up of seminal canals 

 connected and supported by a firm resisting 

 areolar tissue. The ducts which spring from 

 the upper part of the rete testis to form the 

 epididymis are termed vasa cjfcrentia. They 

 are usually about twelve or fourteen in num- 

 ber, but vary from nine to thirty. The inflec- 

 tions of each of these efferent ducts are so 

 arranged as to form in the head of the epidi- 

 dymis a series of elongated conical figures 

 called coni vasculosi. These ducts, at their 

 commencement, run straight for a distance of 

 about one or two lines, when they form con- 

 volutions which become more numerous and 

 close as the ducts recede from the testicle. 

 Their length varies, the upper being the 

 shortest. Lauth found their average length 

 to be seven inches four lines, and calculating 

 their number at thirteen, he makes the united 

 length of the vasa efferentia nearly eight fc'et. 

 He states that the efferent ducts diminish in 

 size from their commencement to their ter- 

 mination in the canal of the epididymis, where 

 they are less than the seminiferous ducts of 

 the testicle. (Fig. 634-.) As in the rete, 

 round dilatations of variable size are often 

 met with in these ducts. (Fig. 632., e c.) 

 The efferent ducts, after forming the coni 

 vasculosi, successively join a single duct, the 

 canal of the epididymis, at irregular distances, 

 the intermediate portions of the duct varying 

 in length from half an inch to six inches. 

 The efferent ducts are more slender than the 

 canal of the epididymis, and frequently give 

 way under the pressure of the column of mer- 

 cury when injected. The body and tail of the 



3 R 2 



