178 



MANUAL OF HISTOLOGY. 



Again, processes of liquefaction and calcification, as well as incipient 

 ossification, are of common occurrence in the costal cartilages of elderly 

 individuals. 



Now, concerning the hyaline cartilages of the larynx, we observe in 

 the larger ones, namely, in the thyroid and cricoid, many layers of small 

 >and narrow flattened cells, immediately beneath the perichondrium, lying 

 in a homogeneous, or occasionally streaky intercellular substance, accord- 

 ing to the direction of the cells. 



The innermost layers, containing daughter-cells, on the other hand, 

 present large and distinct cartilage cells with thickened walls. In older 



Fig. 168. Transverse section of the costal cartilage of an old man. a, homogeneous ground-sub- 

 stance, which has become striated at 6, and has broken into fibres at c ; cartilage-cells may also be 

 seen, possessing for the most part thickened capsules. At d and e, two large parent-cells with nume- 

 rous offspring; another at/, with well-developed laminae in the capsule. 



subjects the intermediate matter may be fibrous or banded ; deposit of 

 fats in the cells is also of frequent occurrence here. Between these two 

 portions, again, is situated a thin layer of larger cells, whose intermediate 

 substance appears granularly clouded (Rheiner). Calcified portions, with 

 finely granular calcareous matter, are also very commonly met with in 

 older individuals ; and true ossification is also seen. The half rings of the 

 trachea correspond with these two cartilages in all essential particulars of 

 texture. 



The texture of the arytenoid cartilages is of great interest, constitut- 

 ing as it does an intermediate form between that just mentioned and 



