192 ANATOMY OF THE DOMESTIC EOWL 



face of the gland. The blood-vessels are not well developed in the 

 interior of the gland but are numerous and of good size in the outer 

 parts. Lymph vessels are also present. 



Function. — The adrenals are ductless glands. They secrete an 

 internal secretion, or hormone, which influences the tonus of the 

 blood-vessels. An extract from these glands is called adrenalin. 



