252 SPECIAL HISTOLOCxY. 



dence of the existence of the same conditions as in man, the 

 Frog, in particular, presents evidence of this fact ; in the tadpole 

 of which, owing to the sparing development of pigment in the 

 tail, the transition of the extremities of the muscular fibres, 

 which are frequently divided into 3 and 5 serrations, into 

 the same number of minute tendons, may be very distinctly 

 seen. In the caudal muscles also, of the Cod, I noticed, very 

 distinctly, the continuous connection of the tendons and mus- 

 cles ; in this case, owing to the shortness of the muscles, many 

 muscular fibres were even seen in their entire length, together 

 with the tendinous fasciculi at each end. 1 ] 



§ 82. 



Accessory organs of the Muscles and Tendons. — A. The 

 muscular envelopes or fascice are fibrous membranes surrounding 

 single muscles or entire groups of muscles, together with their 

 tendons. They differ in structure according to the degree in 

 which they partake of the character of tendons and ligaments, 

 or of simple muscular sheaths ; in the one case presenting that 

 of tendons, and in the other of membranes composed of 

 connective tissue and elastic fibres. In the former case they 

 are white and glistening, and exhibit, in all respects, the struc- 

 ture of tendons and aponeuroses ; in the latter they frequently 



1 [There can be no doubt that both the modes of connection between muscles and 

 their tendons, described above, exist. Is it not possible, that the gradual transition 

 or the sharp line of demarcation between the muscle and its tendon, may have some 

 connection with the age and completeness of the particular bundle examined ? In 

 the Frog, we have noticed that among neighbouring bundles, some exhibit transitions 

 between the proper muscular tissue and the tendon, while others have the former 

 very sharply denned ; and the examination of the insertion of the triceps extensor 

 cubiti of a seven-months' fcetus has afforded us the most evident transitions from 

 tendon into muscle, although the insertion of the bundles is here very oblique 

 (fig. 106 A, 5). The best way of expressing the mode of connection of muscles with 

 their tendons, perhaps, would be to say, that the matrix of the muscle and the matrix 

 of the connective tissue, into which it is inserted (whether in the form of tendon or 

 otherwise, are invariably continuous; the appearance of continuity or of discon- 

 tinuity of the two tissues, arising solely from the sudden or gradual cessation of the 

 deposit of the sarcous elements at their point of junction. 



The nature of the corpuscles which are to be found at the junction of tendons with 

 bones and cartilages — Professor Kolliker's " cartilage corpuscles," — has been adverted 

 to in the note at p. 81. — Eds.] 



