TABLES. 

 BRATA. 



CIRCULATION 



through the System 

 A single but divided 

 branchial heart re 

 ceives the venous 

 blood from the system 

 and propels it to the 

 branchiae ; but there 

 is no S5'stemic heart, 

 the general trunk of 

 the branchial veins 

 being continuous with 

 the aorta, without any 

 intervening dilatation 



MUSCLES, 



frame-work on which 

 they act, and organs 

 of Motion. 

 A regular system of 

 muscles and verte- 

 bratcd skeleton. The 

 vertebral column is 

 very flexible, and is 

 the great instrument 

 of progression. A pair 

 of pectoral and an- 

 other of ventral fins, 

 correspond with the 

 anterior and posterior 

 extremities of quad- 

 rupeds. These are 

 wanting, and the ver- 

 tebral column only 

 in a rudimentary state 

 in some apodal and 

 cartilaginous fishes, 

 which form the link 

 between the vertebra- 

 ta and invertebrata. 



NERVOUS SYSTEM 



and Senses. 

 Brain with medulla 

 oblongata, cerebellum 

 optic tubercles and 

 cerebral hemispheres, 

 but the latter little de 

 veloped ; all the five 

 senses ; spinal cord 

 conveyed on the back 

 of the vertebral co 

 lumn, sending forth 

 from its posterior fila 

 ments, nerves of sen- 

 sation, and from its 

 anterior, nerves of 

 motion. 



Ill 



REPRODUCTION. 



Dioecious and ovi- 

 parous, or in some 

 species ovoviviparous 



A single aortal heart, 

 but branches of the 

 aorta convey a por- 

 tion of the blood to 

 the heart, so that its 

 aeration is only par- 

 tial. 



Regular muscles and 

 vertebral skeleton, 

 with four extremities 

 for locomotion, except 

 in the serpent tribe, 

 which crawl on the ex- 

 tremities of their ribs. 



As in last division, 

 but cerebral hemis- 

 pheres more deve- 

 loped. 



As in last division. 



Double heart, the 

 right ventricle propel- 

 lingtheblood through 

 the lungs and the left 

 ventricle, sending it 

 by the aorta into the 

 general system. 



Regular muscles and 

 vertebral skeleton, 

 with four extremities, 

 the exterior pair con- 

 verted into wings. To 

 give motion to these 

 the muscles of the 

 chest and the osse- 

 ous frame- work are 

 greatly developed ; & 

 for levity the bones 

 are hollow and in- 

 flated with ai r through 

 air cells communicat- 

 ing with the trachea. 



As above, but cere- 

 bral hemispheres still 

 more developed. 



Dioecious and ovi- 

 parous. 



As in last division. 



Regular muscles and I As above. Maxi 

 vertebral skeleton ; mum development of 

 four extremities, (ex- cerebral hemisphere 

 cept in the whale 

 tribe, which want the 

 posterior pair), these 

 are varied to accomo- 

 date them to the pur- 

 poses of walking, 

 climbing, and pre- 

 hension, as the wants 

 of the animal may re- 

 quire. 



Dioecious and vivi- 

 parous. Female pa- 

 rent gives suck to her 

 young. 



