260 



THE VASCULAR SYSTEM. 



(4) The tibio-femoral septum (Septum femoro-crurale) is a circular 

 band, separating the lymph- sacs of the thigh from the leg sac. 



(5) The septa of the foot. At the ankle joint the skin is closely 

 attached all round to the underlying parts. Along the outer border 

 of the foot a septum is attached to the skin externally, and to the 

 underlying parts, especially the M. abductor longus digiti prinii, 

 internally. A similar but weaker band is attached along the outer 

 border of the foot, especially to the M. adductor digiti quinti. 



b. The lymph-sacs. 



(i) The femoral lymph-sac (Saccus femoralis), (Figs. 169, 170, 

 171, 175 9) covers the lower and outer surfaces of the thigh ; it is 



bounded by the superior femoral and 

 inferior femoral septa, and in front 

 ;m by the inguinal septum. 



(2) The suprafemoral lymph-sac 

 u (Saccus suprafemoralis], (Figs. 169, 

 171, 175 10) lies on the upper sur- 



face of 



thigh, between the 



s ri f 



Transverse section of the thigh. 



1) M. biceps. 



/' Superior femoral septum. 



/'' Inferior femoral septum. 



/" Intermediate femoral septum. 



H Skin. 



ri' M. rectus internus major. 



ri'" M . rectus internus minor. 



s M. Sartorius. 



sm M. semimembranosus. 



ve M. vastus externu s. 



9 Femoral lymph-sac. 



10 Suprafemoral lymph-sac. 



1 1 Interf em oral lymph-sac. 



the 



superior and intermediate femoral 

 septa; above it is bounded by the 

 inguinal septum. 



(3) The inter-femoral lymph-sac 

 (Saccus interfevioralis), (Figs. 169, 

 170, 175 n) is a narrow sac on the 

 inner surface of the thigh, between 

 the inferior femoral septum and the 

 intermediate femoral septum. It 

 covers the M. rectus internus minor, 

 and is interrupted by numerous bands of tissue which pass from the 

 surface of the muscle to the skin. It is, therefore, not a simple sac, 

 but a very wide-meshed trabecular structure of connective-tissue. 

 The sac is triangular in shape, with the base directed forwards at 

 the inguinal septum. 



(4) The lymph-sac of the leg is a simple sac enclosing the 

 whole leg, bounded above by the tibio-femoral septum, and below by 

 the attachment of the skin to the ankle. 



(5) The lymph-sacs of the foot. On the dorsum of the foot the 

 skin is free, and there is consequently a lymph-sac. On the plantar 

 surface the skin is attached by numerous connective-tissue bands 

 and thread-like tendons, particularly to the flexor tendons. The 



