84 FLASK-LIKE SECKETING CELLS. 



amyloid, fatty matter, the resinous salts of the bile, and 

 colouring matters. 



125. Flask-like Secreting Cells. Another, type of 

 secreting cell is that in which the secretion is poured 

 into the interior, and, after accumulation, discharged 

 from a free opening at its extremity, the cell remain- 

 ing for some time a fixture, and continuing to dis- 

 charge its office. In the mouth of the boa these cells 

 attain a very high degree of development, and are 

 of large size. They also exist in great number, and 

 some may be found in every stage of formation; 

 for, although each one may perform its work for a 

 certain period of time, the cells are being continually 

 removed and replaced by new ones which grow up 

 from below. 



Like all other elementary parts or units, these 

 flask-like cells exist first as spherical or oval masses 

 of bioplasm, which then become altered upon the 

 surface, and the formed material constituting the 

 "cell wall" is produced. In this cavity products 

 resulting from the change of the bioplasm at its distal 

 extremity accumulate, and the cavity becomes di- 

 lated. The accumulation of contents and enlarge- 

 ment of the space proceed till at last the summit of 

 the cell approaches the surface ; an opening is then 

 formed at its free extremity, and the contents are 

 discharged. These cells remain for some time in 

 position, constantly discharging the secretion which is 

 being formed by the bioplasm in their interior. The 

 bioplasm remains near the lower attached extremity 

 of the open-mouthed cylindrical cell, and takes up 

 nutrient matter at its lower surface, while at its 

 upper part, which forms the floor of the cell cavity, 

 the bioplasm is gradually changed into the secretion 

 of the cell. This accumulates in the cavity, and 

 gradually escapes from the open orifice. A large 

 quantity of pabulum may pass into the state of bio- 

 plasm, and a corresponding quantity of the latter 



