964 MALE ORGANS OF GENERATION. 



it lies in front of the conjoined tendon of these muscles, the fibres of which 

 have arched inwards over it, and its creniasteric covering, is in contact 

 anteriorly with the aponeurosis of the external oblique muscle. The inguinal 

 canal is therefore said to be bounded posteriorly by the fascia trans versalis 

 above and the conjoined tendon below, and anteriorly by fibres of the 

 transversalis and internal oblique muscles above, and the aponeurosis of the 

 external oblique muscle below ; while its floor is formed by the curving 

 backwards of Poupart's ligament, and its roof by the apposition of the layers 

 of the abdominal wall. 



As it enters the inguinal canal, the cord receives a covering from the 

 infundibuliform fascia, a thin layer continuous with the fascia transversalis, 

 and prolonged down from the margins of the de, j p abdominal ring ; within 

 the canal it receives a covering from the cremaster muscle and fascia con- 

 nected with it ; and as it emerges from the canal there is added, superficially 

 to this, the intercolumnar fascia prolonged from the pillars of the superficial 

 abdominal ring. 



The scrotum. The scrotum forms a purse-like investment for the testes 

 and part of the spermatic cords. Its condition is liable to certain variations 

 according to the state of the health and other circumstances : thus, it is 

 short and corrugated in robust persons and under the effects of cold, but 

 becomes loose and pendulous in persons of weak constitution, and under the 

 relaxing influence of heat. Its surface is marked off into two lateral halves 

 by a slight median ridge, named the raphe, extending forwards to the 

 under side of the penis, and backwards along the perinseum to the margin of 

 the anus. 



Within the scrotum, the coverings of the cord and testis, as enumerated 

 from without inwards, are the skin, superficial fascia and dartos tissue of the 

 scrotum, the intercolumnar fascia, the cremaster muscle and cremasteric 

 fascia, and the infundibuliform fascia, which is united to the cord by a 

 layer of loose areolar tissue ; lastly, the testicle has a special serous tunic, 

 named the tunica vaginalis, which forms a closed sac, and covers the tunica 

 albuginea or proper fibrous coat of the gland. 



1. The skin in this situation is very thin, and is of a darker colour than 

 elsewhere ; it is generally thrown into rugse or folds, which are more or less 

 distinct according to the circumstances already mentioned. It is furnished 

 with sebaceous follicles, the secretion from which has a peculiar odour, and 

 it is covered over with thinly scattered crisp and flattened hairs, the 

 bulbs of which may be seen or felt through the skin when the scrotum is 

 extended. The superficial blood-vessels are also readily distinguished 

 through this thin integument. 



2. Immediately beneath the skin of the scrotum there is found a thin 

 layer of a peculiar loose reddish-brown tissue, endowed with contractility, and 

 named the dartos tunic. This subcutaneous layer is continuous with the super- 

 ficial fascia of the groin, perinseum, and inner side of the thighs, but acquires 

 a different structure, and is perfectly free from fat. The dartoid tissue is 

 more abundant on the fore part of the scrotum than behind, and, moreover, 

 it forms two distinct sacs, which contain the corresponding testes, and are 

 united together along the middle line so as to establish a median partition 

 between the two glands, named the septum scroti, which is adherent below to 

 the deep surface of the raphe and reaches upwards to the root of the penis. 

 The dartos is very vascular, and owes its contractile properties to the 

 presence of a considerable amount of unstriped muscular tissue. Its con- 

 tractility is slow in its action ; it is excited by the application of cold and of 



