SKBLBTO-TROPHIC TISSUES AND OOXAL GLANDS. 149 



anything corresponding to the general matrix of a hyaline 

 cartilage. The capsules are all closely packed, without giving 

 rise to any quantity of homogeneous inter-capsular substance. 



They resemble in this the cell-walls of vegetable parenchyma. 

 In another respect, also, the capsules resemble vegetable cells, 

 and differ from typical Vertebrate cartilage. The protoplasm 

 does not fill its capsule. A large cavity unoccupied by 

 protoplasm exists in all the larger capsules (PI. XI, fig. 4, e). 

 Further, just as vegetable cell-walls break down, so as to place 

 neighbouring cells in communication, and thus constitute ducts 

 and vessels, so here do we find the walls of the capsules often 

 incomplete, probably always becoming so after a time (PI. XI, 

 fig. 7). Thus the space or cavity unoccupied by protoplasm in 

 each capsule is placed in continuity with the similar space in 

 neighbouring capsules. These communications are not, as the 

 comparison to vegetable ducts might lead it to be inferred, 

 arranged in a straight line, but, in accordance with the triaxial 

 growth and expansion of the tissue, they are developed in all 

 directions. 



The protoplasm lying within each capsule is disposed all 

 round the capsule as a " primordial utricle," and fills usually 

 about half its cavity. The space not occupied by the proto- 

 plasm is occupied by a thin liquid common to the whole sys- 

 stem of communicating capsules. There is no special feature 

 calling for remark about the nuclei, the character of which is 

 seen in the drawing, PI. XI, fig. 4. 



Where the capsuligenous tissue is in contact with the fibi'oid 

 tissue of the cortical layer of the entapophysial ligament it is 

 seen that the substance of the capsule is continuous with the 

 intercellular fibroid matrix of the fibroid tissue (PI. XT, 

 fig. 4 r). 



A little reflection renders it evident that the plan of struc- 

 ture of the capsuligenous tissue is essentially the same as that 

 of the lacunar connective tissue above described (Sect. 3). 

 Were the capsules of the capsuligenous tissue much larger, and 

 the skeletal substance of which they are composed less dense 

 and more delicate, and were the proliferating cell-units of pro- 



