XXVI 



CONTENTS. 



Paragraph 



410. 

 411. 412. 



413. 

 414—416. 



417. 



418. 



419. 



420. 



421. 



422. 



423. 



424. 

 425^27. 



428. 

 429. 430. 

 431—436. 

 437—442. 

 443—446. 

 447—449. 

 450—458. 



Pag© 



Branchial clefts and palate of the Amniota .... 545 



Nasal cavity ^4' 



Buccal cavity .....•••••• 548 



Organs of the buccal cavity 549' 



Alimentary canal proper (Enteron of the trunk) .... 555 



Fore-gut .......•••• 556 



ilid-gut 559 



Hind-gut 561 



Organs appended to the mid-gut 563 



Mesentery ......••••• 565 



Pneumatic organs of the enteric tube 566 



a) Air-bladder 567 



b) Lungs ......•••••' 569 



Ccelom 574 



Vascular system 575 



Heart and arterial system 577 



Venous system 589 



Lymphatic system • 59/ 



Excretory organs 601 



Generative organs 608 



