CONNECTIVE TISSUE. 207 



tinctly granular, but in some portions finely striated. The homogeneous or 

 indistinctly granular-looking basis-substance is that which bears the name 

 hyaline basis-substance ; the striated is termed fibrous, although actual fibrillee 

 appear only on the edges of the specimen, or when the tissue is torn and 

 mutilated. The fibrous basis-substance is intermixed, without any regularity, 

 with the hyaline, and usually sharply separated from it. Not infrequently a 

 number of cartilage corpuscles, or groups of cartilage corpuscles, are sur- 

 rounded by fibrous basis-substance, the striations of which run, as a rule, in 

 a sagittal direction, i. e., vertical to the surface. Within the fibrous basis- 

 substance the cartilage corpuscles are at most points sparsely scattered or 

 absent ; here and there, however, they are more numerous, in rows or elon- 

 gated, corresponding to the direction of the striations. It also occurs that 

 striated portions of the basis-substanee contain very minute globular or 

 oblong corpuscles, sometimes to such an extent that the striated structure is 

 concealed by the large number of these corpuscles. (See Fig. 79.) 



The fibrous portion is seen to occupy the center of a longitudinal section 

 of one of the plates of the thyroid cartilage. This is not regularly the case 

 in every cut, and was exceptionally well marked in the section from which 

 the drawing was made. In some sections the fibrous cartilage is altogether 

 absent, but every laryngeal cartilage contains some fibrous mixed with hya- 

 line portions. 



Under higher magnifying powers (500 to 600 diameters), single cartilage 

 corpuscles exhibit features, frequently before described, with coarsely granu- 

 lar nuclei. Around the nucleus finer granules are visible. At the periphery 

 of the cartilage corpuscle there are several strata of higher refracting power, 

 especially the zone nearest the basis-substance, which, as a rule, appears 

 very shining and is what is termed the capsule of the cartilage corpuscle. 

 Not infrequently the cartilage corpuscle is very indistinct, being but slightly 

 more granular than the surrounding basis-substance ; then almost nothing 

 but the nucleus marks its presence and its place. In twin formations of car- 

 tilage corpuscles, which are often met with, the zone of division between the 

 two corpuscles is identical with that surrounding both, in the shape of a cap- 

 sule. Of the same nature are the zones of division that are seen in clusters 

 of cartilage corpuscles. 



The so-called hyaline basis-substance throughout its whole extent now 

 appears finely granular ; as a rule, the granulation is more distinct midway 

 between the corpuscles than in their immediate vicinity. The fibrous por- 

 tions of the basis-substance are seen to be made up of extremely minute 

 spindles, which, by being grouped longitudinally, produce the aspect of 

 striation. The spindles or fibers are separated from each other by light 

 rims, and both the spindles and the rims look finely granular. Between the 

 spindles may often be seen small globular bodies, sometimes scattered, some- 

 times in clusters, of which the size and shape greatly vary, reaching occa- 

 sionally the size and shape of a regular cartilage corpuscle. In some striated 

 fields, blood-vessels, both arterial and capillary, can be seen ; the former with 

 the characteristic muscle-coat, the latter with the endothelial wall, besides 

 holding red blood-corpuscles in their calibers.* 



The highest powers of the microscope (1000 to 1200 diameters) reveal 



* These striated fields are remnants of former medullary spaces, for the striated portions 

 in the center of the cartilage never contain Wood- vessels. 



