246 



SrECIAL HISTOLOGY. 



Fig. 95. 



O006 — O008"' and a rounded polygonal figure, as may be 

 seen, especially in transverse sections of dried tendons, par- 

 ticularly on the addition of alkalies. But in the natural state, 

 they are so firmly united that they cannot be isolated. 



On the other hand, in true tendons, in the recent state, 

 secondary and tertiary fasciculi are very evident (fig. 95). 

 Delicate dissepiments, in fact, of loose connective tissue, 

 penetrate the substance of the tendon, and by their mutual 

 connection form a continuous system of parallel tubes, thus 

 dividing the tendinous fibrils or primitive fasciculi into numerous 

 larger or smaller groups. Secondary fasciculi, mostly of a 

 polygonal, or perhaps rounded or elongated figure, and having 

 a diameter of - 03 — O06'", may be very readily distin- 

 guished ; and tertiary fasciculi, with polygonal contours, of 

 0-1 — 0-05'" and more in diameter, and bounded by rather 



stronger dissepiments; 

 there are, also, general- 

 ly apparent, still larger 

 subdivisions, composed 

 of numerous tertiary 

 fasciculi, and which 

 being closely united in 

 very various numbers 

 and groups, by a com- 

 mon envelope of lax 

 connective tissue, con- 

 stitute the tendon it- 

 self. The aponeuroses 

 are constituted either 

 in the same way as 

 the true tendons, and 

 consist of several layers 

 of parallel, secondary 

 fasciculi, disposed contiguously in the same plane; or, more 

 resemble the fibrous membranes, and present primary and 

 secondary fasciculi decussating in two or more directions 

 (abdominal muscles, diaphragm). 



Fig. 95. Transverse section of a tendon of the calf, x 20 diam.: a, secondary 

 fasciculus; b, tertiary; c, nuclear fibres not quite in transverse section, but appearing 

 as little streaks in the former ; d, interstitial connective tissue. 



&..J 



