GENERAL INDEX 527 



Heterostraci, 29, 275, 326, 343 



Hirudinea, 478 



Histolysis in transformation of the lamprey, 59 



Homology of branchial region of vertebrate and invertebrate, 149 



,, ductless glands and nephridial organs, 418 



,, external genital ducts of arthropods and nephridia of annelids, 429 



,, germinal layers in all Metozoa, 459 



,, pituitary body of Arnrnoccetes and coxal glands of Limulus, 319 



,, tubular muscles of Arnrnoccetes and veno-pericardial muscles of 



Limulus, 309 



,, ventral aorta of vertebrate and longitudinal venous sinuses of Limulus, 



178 

 Hydra, 441, 465, 472, 470 

 Hydrophilus larva, eye, 84 

 Hyoid segment in Arnrnoccetes, 186, 267 

 Hypoblast, 434, 438, 444, 445, 459 

 Hypoctonus, cartilage cells in entosternite, 133 



operculum, 189, 207 

 Hypogastric plexus, 3 

 Hypogeophis, 393 

 Hypophysis, 229, 244, 317, 318, 340 



Inpundibulum, position, 122, 132 



,, tube, the ancestral oesophagus, 4, 37, 244, 318 



,, ,, relation to neural canal, 14, 36, 318, 440, 457 



notochord, 318, 435, 440 

 olfactory tube, 220, 22S, 318, 340 

 Insects, chordotonal organs, 364, 370 

 Invertebrate, heart, 175, 179 



,, excretory organs, 418 



,, nervous system, 13, 54 



segmental nerves, 152 



-,-,1 



Kekaspis, 75, 328, 338 

 Kidney, 420, 459, 476 



,, nerves, 477 

 King-crab, v. Limulus 



Labykinthodont, 21, 28 



Lamina terminalis, 49 



Lamprey, v. Arnrnoccetes and Petromyzon 



Larva, v. Transformation of the Lamprey 



Lateral line system, 261, 355, 411, 470 



Law of Progress, 19 



,, Recapitulation, 434, 456, 498 

 Layer, germinal, 459 



,, laminated, 347, 348 

 Leech, 421 



Lens, formation, 83, 115 

 Lepidosiren, 148, 461, 466 

 Limulus or king-crab, 25, 140, 236, 240 



„ appendages, branchial, 138, 164, 175 



