OECELLA. 385 



tips of the . arytenoids which lay in two depressions on its upper surface 0'15 

 inch behind its free margin; whereas in the adult they completely overlay the 

 epiglottis with their tips nearly on a line with its free margin. In the foetus they 

 were also much more bent down upon the epiglottis than in the adult. The epiglot- 

 tis too, instead of having its thick margin reverted and strongly projecting as is 

 the case in the adult, in the foetus was flush with the rest of the tube. The 

 epiglottis differs from that of Platanista gangetica in being relatively broader and 

 in its external angles being much thicker and prolonged further into the free 

 margin of the aryteno-epiglottidean membrane. 



On opening into the larynx (fig. 2) a remarkable and beautiful structure was 

 displayed, hning the lower part of the cartilage of the epiglottis and the aryteno- 

 epiglottidean membrane and the whole floor of the cavity, and part of the sides 

 of the cricoid cartilage. A strong fold arising by three origins from the lower 

 third of the cartilage of the epiglottis is attached along that cartilage to its 

 base, where it gives off a series of short folds, three of which occur on the left 

 and one on the right side. The most anterior of the former is attached to the 

 base of the aryteno-epiglottidean membrane, and the two others to the main border 

 of the base of the body of the arytenoid. The fold of the opposite side is attached 

 to the same portion of the last mentioned cartilage of the right side, but it gives 

 off four fine septal folds from its outside, which are prolonged up the sides of 

 the cartilage of the epiglottis. These folds are connected together by transverse 

 tendinous folds, which constitute little recesses by the generally arched lower border 

 being free. Indeed this part of the structure has a close resemblance to the 

 structure of the guttural eustachial pouch of Flatanista. On the left side, only 

 the most anterior fold gives off a tendinous fold, which runs up the side of the 

 cartilage of the epiglottis, and has the same structure as already described on 

 the right. The central fold is continued backwards between the base of the 

 arytenoids as a thin sharp ridge-like fold, but behind that point it gradually 

 expands, and about an inch behind the arytenoids divides into a number of tendin- 

 ous-looking bands. Radiating from the posterior border and base of the arytenoids, 

 and passing backwards along the sides and floor of the cavity, are numerous strong 

 bands which die away posteriorly at the first ring of the trachea. These folds are 

 connected together on the floor of the cavity by arched transverse folds and these 

 again by secondary folds, so that a deeply honeycombed structure is produced, 

 the space defined by the last mentioned folds constituting a series of deep pockets^ 

 pits or crypts. The folds when viewed with a hand lens are seen to be thrown into 

 more or less exceedingly fine transverse rugse. On making a vertical section through 

 the larynx, it is demonstrated that none of the deep pits communicate with any air 

 sac, nor is there any trace of such a structure. The floor of the larynx above the 

 cricoid, from the base of the arytenoids backwards for some distance, presents 

 a glandular structure, divided off into lobules presenting open orifices. Imme- 

 diately below the base of the arytenoids, several orifices appear separated from 

 each other by fine septa, and it is apparent that they form a complex series of 



A3 



