QUARTERLY CHRONICLE OF MICROSCOPICAL SCIENCE. 179 



avachnoitl, and the cells are of a rounder shape, so that the 

 formation of fibres takes place rather in all directions than in 

 any particular one. 



In the tendon the cells lie not only at first but perma- 

 nently very close together ; and hence the difficulty in 

 making out the relations of fibres to cells. In general, the 

 appearance is that of a band composed of parallel fibres, in 

 which are imbedded numerous nuclei ; but here, also, in 

 favorable objects it may be clearly made out that the fibrillse 

 compose the body of the cell. As, however, the development 

 of fibres takes place chiefly on one side, ultimately, when the 

 cell and the fibres are distinct, the former seems as if applied 

 to the side of the latter. 



It seemed here also as if long fibres were made up by the 

 union of numerous shorter scjiinents. No granule-cells are 

 seen in tendon, and thus there appears to be an important 

 difference between the development of this tissue and tluxt 

 of the arachnoid, and, in consequence of this, the embryonic 

 cells do not, as in the arachnoid, disappear, but remain 

 attached to the fibrous bundles as above described. 



Tendon.— Torok (' Centralblatt,' No. 5,1872, p. 66) has 

 published a preliminary notice of researches on the Achilles 

 tendon in the frog, enumerating the following points: — (1) 

 He agrees with Boll in rejecting Kanvier's " tubes cellulaircs." 

 (2) He finds the technical precautions recommended both by 

 Ranvier and Boll, in regard to stretching the tendon, fixing 

 it with sealing-wax, &c., quite unnecessary, nor does he think 

 the difference in structure between the lax and tense tendon 

 of any importance. (3) The cells are not so peculiar as to 

 deserve any special name, such as " endothelioid," and 

 the " elastic stripe " of Boll is simply a fold, (4) The 

 peculiar structure resembling a sesamoid bone in the Achilles 

 tendon of the frog is true cartilage, both anatomically and 

 chemically, but diff"ers a good deal in different species of 

 frog; it is sometimes ossified. According to the author, 

 Heiile twenty years ago was inclined to adopt the hypothesis 

 of cellular tubes in the tendons put forward anew by Kan- 

 vier, but rejected it on further examination ; and in the same 

 way recognised and correctly described Boll's "elastic stripe" 

 as a fold. 



Ponfick C Centralblatt,' No. 8, 1872) has published a 

 preliminary notice of some researches on tendon, chiefly with 

 reference to the views of Ranvier and Boll. He agrees in 

 the main with the results of Torcik, given above, but suggests 

 another explanation of the " elastic stripe" of Boll, also believ- 

 ing it to be an optical illusion. He believes the lateral 



