528 THE ORIGIN OF VERTEBRATES 
Limulus appendages, prosomatic, 381 
» brain, 54 
», circulation, 174, 176 
» Classification, 26, 249 
», celomic cavities, 252, 328 
»  coxal glands, 321, 389, 397, 403, 429 
» eyes, median, 62, 74, 81 
», entosternite or plastron, 142, 148 
» flabellum, 360, 362, 363, 380, 381 
» generative organs and ducts, 189, 202, 208, 209, 380 
» heart, 180 
» musculature, branchial, 170 
” ” prosomatic, 247 
a5 - veno-pericardial, 177, 297, 309, 313 
»  lerves, appendage, 140, 157 
4s » cardiac, 314 
3 » segmental, tripartite division of, 157, 235, 267, 355 
» segments, branchial, 152 
i 5 first mesosomatic, 188 
9 i prosomatic, 233 
» operculum, 189, 202, 235, 295 
5  sense-organs, poriferous, of appendages, 359 
Lip, lower, of Ammoceetes, 246, 289, 297, 458 
» Upper, 35 228, 243, 303, 336 
Liver, Ammoccetes, 452 
» Limulus, 209, 211 
Lizard, pineal eye, 80 
»  suprarenals, 424 
» tail, 50 
Lobes, optic, 101 
Lobster, 489 
Lungs, 148 
Lung-books of scorpions, 150 
Lymph, 474 
Lymph-corpuscles, 463, 490 
Lymphocytes, 472 
MALAPTERURUS, 470 
Mammal, dominance of, 21 
Man, dominance of, 17 
Marsipobranchs, 23, 35 
Medullation of nerve-fibres, 20, 267, 467, 477 
Membranes, basement, 436 
Meroblastic egg, 485 
Merostomata, 25, 249, 321 
Mesencepalon, 48 
Mesoblast, 444, 455, 459 
Mesogloa, 474 
Mesonephros, 389, 400, 424, 429 
Mesosoma, 52 
Mesothelium, 472, 477 
Metanephros, 389 
