324 



THE ELASMOBRANCH FISHES 



Gill pocket, 147, 150; accessory, 151; 



apertures of, 147, 151; development of, 



151; fiiaments on, 147; in Heptanchus, 



147 

 Gill rakers, 37, 147, 154; of Cetorhinus, 



37, 154; of Squalus sucklii, 37, 154 

 Gill septum, 147, 148-149; attachment of, 



149 

 Gill supports, 148 

 Gland cell, 23, 28; in buccal cavity, 28; 



in cloaca, 28; lumen of, 28; modified, in 



light organs, 29; of claspers, 28; of 



sting, 28; origin of, 28 

 Glomeruli of olfactory bulb, 239, 264 

 Glomerulus, 296, 299 

 Glossal projection, 65 

 Glossopharyngeal nerve, 225, 243-244; 



branches of, 225, 244; ganglion of, 225, 



244; nucleus of, 243 

 Goblet cells. See Gland cells 

 Golden cells, 27 

 Grey matter of cord, 237 

 Guanin, 27 

 Gular line, 263 



Gustatory organs, 264, 265-266 

 Gynandromorphism, 309 



Habenular ganglion, 236 



Haemal arch, 47 



Haemoglobin, 170 



Hair cell, 273, 278; of ampulla, 273; of 

 neuromast, 278 



Hammerhead shark (Zygaeno), 2. 



Head somite, 99 



Heart, 160, 170-172; arteries to, 163-164, 

 178-180; nerves to, 227; position of, 

 160; rooms of, 160, 170; veins of, 215- 

 216 



Hepatic artery, 166, 187 



Hepatic portal system, 200, 204, 210-212; 

 development of, 212; parts of, 200- 

 201, 210-212; relation of, to subintes- 

 tinal, 208, 212 



Hepatic portal vein, 201, 211; tributaries 

 of, 211 



Hepatic vein, 200, 201, 211, 213 



Heptanchus, figs. 12, 13, 14, 15 



Heptanchus maoulatus, 2, 3; antorbital 

 process of, 44; arteries of, 161-169; 

 digestive tract of, 121-126; endoskele- 

 ton of, 43-52; external form of, 5-7; 

 genital system of, 290-291; integument 

 of, 23-25; musculature of, 89-95; ner- 

 vous system of, 221-228; respiratory 



tract of, 147-149; special senses of, 



258-263; veins of, 198-203 

 Heptranchias, 3 note 

 Heterocercy, 74 

 Heterodontus francisci, 2, fig. 17; egg case 



of, 305; melanophores of, 27; teeth of, 



130 

 Hexanchus, 2, 3 ; hypobranehial arteries 



of, fig. 169 

 Hindbrain, 230 

 Holobranch, 148 

 Horizontal semicircular canal, 258, 273; 



development of, 274 

 Horns of cord, 222, 237; dorsal, 222, 237; 



ventral, 222, 237 

 Hymen, 309 

 Hyoid arch, 45, 63; attachment of, 45, 



58, 63; muscles of, 92 

 Hyoidean afferent artery, 161, 172 

 Hyoidean ampullae, 279-280 

 Hyoidean efferent artery, 165, 182 

 Hj-oidean nerve. See Eamus hyoideus 



(VII) 

 Hyoidean sinus, 208 

 Hyoidean somite, 99 

 Hyoidean vein, 208 

 Hyomandibula, 63-64 

 Hyomandibular canal, 261, 274, 277; 



modification of, in rays, 277; nerves to, 



224, 242, 243, 279 

 Hyomandibular nerve, 224, 242, 243; 



branches of, 224; foramen of, 44 

 Hypobranehial arteries, 162-165, 178- 



180; lateral, 163, 178; median, 163, 179 

 Hypobranehial cartilages, 45-46, 64, 65; 



attachment of, 46; muscles to, 94 

 Hypobranehial muscles, 90, 93, 108-109; 



nerves to, 227, 246; origin of, 108 

 Hypophysis, 233; divisions of, 233 



Iliac artery, 169, 192 



Iliac vein, 213 



"Indifferent stage" of sex, 300 



Inferior jugular vein, 199, 204; tributaries 



of, 199 

 Inferior lobes of brain, 221, 233 

 Inferior lobes of hypophysis, 234 

 Inferior mesenteric artery, 167-168, 186, 



190-191 

 Inferior oblique muscle, 89, 100; in Pris- 



tiophorus, 100; origin of, 99; nerve to, 



100, 223, 239-240 

 Inferior rectus muscle, 90, 99; origin of, 



99; nerve to, 100, 223, 239-240 



