THE SCROTUM. 139 



muscle. 3. The tunica vaginalis communis, so called from its 

 covering in closely both the cord and testicle of each side, 

 and sometimes named tunica elythroides, from the cremaster 

 muscle which is spread over it. 4. Of the tunica serosa or 

 tunica vaginalis testis and 5. Of the tunica albuginea } or 

 proper coat of the testicle. 



That portion of the common integuments which forms the 

 external covering of the testicles, is denominated, 



The Scrotum. 



The skin of the scrotum, although it is very often in a state 

 of corrugation, has the same structure with that on other parts 

 of the body, except that it is rather thinner and more delicate. 

 The superior delicacy of this portion of the skin is evinced by 

 the great irritation produced by the -application of stimulating 

 substances, and the desquamation of the cuticle, which seems to 

 be the effect of irritation. There are many sebaceous follicles 

 in this portion of skin ; and after puberty there are often a few 

 long hairs growing out of it, the bulbs of which are often very 

 conspicuous. There is a small raised line in the middle of this 

 skin, which commences at the root of the penis, and proceeds 

 backwards, dividing it into two equal parts: this line is denomi- 

 nated Raphe. 



The corrugation which so often takes place in the skin of the 

 scrotum, appears to be occasioned by the contraction of certain 

 fibres, which are in the cellular substance immediately within 

 it. This cellular substance appears to be attached in a parti- 

 cular way to the skin ; and it also invests each testicle in such 

 a manner, that when they are withdrawn, a cavity is left in it. 

 It has long been observed, that no adipose matter is found in 

 this cellular substance : but it is often distended with water in 

 hydropic diseases. As the contraction and corrugation of the 

 scrotum has been imputed to this substance, it has been exam- 

 ined with particular attention by anatomists, and very different 

 sentiments have been entertained respecting it. While 

 some dissectors have asserted that muscular fibres could be 

 seen in it, which they have denominated the Dartos Muscle ; 

 others have said that this substance was simply cellular, and 



