522 
THE ORIGIN OF VERTEBRATES 
Ccelom, 167, 251, 400, 472, 481 
Celomata, 472 
Coslomoceela, 472, 475 
Ceelomostomes, 477, 481 
Colleneytes, 474 
Commissure, anterior, 49 
” 
cesophageal, 14 
a posterior, 48, 280 
Comparison of brains of Ammoccetes and Arthropod, 61 
” 
Corneagen, 69 
rn invertebrate from Branchipus to Ammoceetes, 54 
“4 vertebrate, 40 
branchial circulation in Ammoccetes and Limulus, 174 
5 lamelle of Scorpion and Ammoccetes, 175 
- segments of Ammoccetes and Petromyzon, 169 
Cephalaspidian and Paleostracan fish, 31 
Ceelom of Peripatus and Vertebrate, 400 
dermal covering of Pteraspis with chitin of Limulus or dentine of fish 
scales, 346 
ee or plastron of Limulus with trabecule of Ammoccetes, 
14 
excretory organs of vertebrates and invertebrates, 389 
gut of Arthropod and tube of central nervous system of Vertebrate, 48, 
244, 483, 440, 455, 457 
head-shield of Cephalaspis and Ammocetes, 291, 329, 338 
hypophysial tube with olfactory tube of Arthropod ancestor, 229 
5 », With position of paleostoma, 317 
mesosomatic region of Ammoccetes and Hurypterus, 192 
muscles, branchial, of Ammoccetes and appendage muscles of Scorpion, 
171, 447 
eye, of Vertebrate with dorso-ventral muscles of Scorpion, 
267, 272, 459 
of oral chamber of Ammoccetes and prosomatic musculature 
of Limulus, 247, 447 
longitudinal body-muscles of Vertebrate and dorsal longi- 
tudinal muscles of Arthropod, 411, 447 
nerves, appendage of Limulus and Branchipus to lateral root system 
of Vertebrate, 157 
» cranial and spinal segmental, 152 
nervous systems of Vertebrate and Arthropod, 36 
pineal gland of vertebrates and median eyes of Arthropod, 63, 456 
pituitary body and coxal glands, 246, 319, 321 
prosoma and mesosoma of Limulus and Ammoceetes, 140, 144 
prosomatic region of Ammoccetes and Hurypterus, 244, 338 
retina in Ammoccetes and Musca, 97 
», compound in Arthropod and Vertebrate, 87 
skeleton of Limulus and Ammoccetes, 126, 136 
sense-organs of Arthropod appendages with auditory organs of 
Vertebrate, 375 
thyroid with endostyle, 198 
uterus of Scorpion, 205 
” 
” 
” ” 
Corpora quadrigemina, 47 
