Ductless^ or Vascular Glands, 97 



is persistent and large in 



all diving animals ; e.g. Castor (Eodentia), Lutra and Plioca 

 (Sectorialia), and Cete. 



In the Artiodactyla,- whether Euminantia or Omnivora, the cer- 

 vical portions of the Thymus are much developed, often extending 

 to the mandibular angles. 



4. The Supra-Renal Capsules 



are generally present, and always larger in the foetal tlian 

 in tlie adult animal : in lower Mammals they are not alwaya 

 in contact with, the kidney, as they are in Man. 



