GLANDULAR SYSTEM. 275 



A. It does not. That operation is the result of vital ac- 

 tion; still the motion given to some glands may be acces- 

 sory to excretion. 



Q. Under what circumstances is this accessory motion 

 necessary ? 



#. It is found wherever the parietes of the organ are 

 not very powerful. 



Q. Besides the division of glands into sub-cutaneous 

 and deep-seated, there is another, what is it? 



V?. Into single and double glands. The liver is a single 

 gland; the kidneys are double, in pairs. 



Q. Is there the exact symmetry in two glands of the 

 same pair as is found in the organs of animal life? 



#. There is not; because the harmony of action in ani- 

 mal life requires the utmost exactness. 



Q. What circumstance materially controls these varie- 

 ties of form in the glandular tissue? 



*fl. The fact of their being invested by a strong mem- 

 brane has great influence in this respect. The liver, which 

 is contained in a membrane, has much fewer varieties than 

 the lachrymal, or the salivary, which are without such in- 

 vestment. 



Organization of the Glandular System. 



Q. In what is the texture of the glands peculiar? 



#. The oblique or longitudinal fibrous linear arrange- 

 ment met with in the muscular, osseous, nervous tissues,- 

 is not seen at all in the glands. They are agglomerated, 

 and slightly united by cellular texture. 



Q. How is the parenchyma of glands to be divided? 



rf. Into three forms. 





