LIST OF ILLUSTRATIONS. xvn 



FIG. 



. 



249. Side view of chief cranial nerves of Elasmobranchs (slightly 



modified from Cossar Ewart) . 5 21 



250. Spiral valve of skate (T. J. Parker) . . 522 



251. Upper part of the dorsal aorta in the skate (Monro) . . 523 



252. Heart and adjacent vessels of skate (in part after Monro) . 524 



253. Urogenital organs of male skate . . . 5 2 5 



254. Urogenital organs of female skate (in part after Monro) . 526 



255. Elasmobranch development (Balfour) . . 527 



256. Embryo dogfish in egg-case (" Mermaid's purse") which has 



been cut open to show contents ..... 528 



257. The haddock ...... . 530 



258. External characters of a Teleostean a carp (Leunis) . . 530 



259. Caudal vertebra of haddock ... . . 531 



260. Disarticulated skull of cod . . . 532 



261. Pectoral girdle and fin of cod . . . 533 



262. Diagram of Teleostean circulation (Nuhn) . . . 535 



263. The early development of the salmon . .... 538 



264. Young skate (Beard) . ... . 547 



265. Lateral view of dog-fish (Scyllimn catnlits) . . . 548 



266. Outline of Acanthodes sulcatus (Traquair) .... 548 



267. Sturgeon (Acipenser sturio) ... . . 550 



268. The Gold-fish (Cyprinus auratns} ..... 552 



269. Skeleton of Ceratodits fin (Gegenbaur) . . -554 



270. Head region of Protopterus (W. N. Parker) . . . 555 



271. The Edible Frog (Rana esciilenta] ..... 560 



272. Vertebral column and pelvic girdle of bull- frog . . . 562 



273. Skull of frog upper and lower surface (W. K. Parker) . 563 



274. Skeleton of frog ........ 565 



275. Pectoral girdle of Rana esciilenta (Ecker) .... 566 



276. Side view of frog's pelvis (Ecker) ..... 566 



277. Brain of frog (Wiedersheim) ...... 567 



278. Nervous system of frog (Ecker) ...... 568 



279. Arterial system of frog ....... 572 



280. Venous system of frog ....... 573 



281. Urogenital system of male frog (Ecker) .... 577 



282. Urogenital system of female frog (Ecker) .... 577 



283. Division of frog's ovum (Ecker) . ..... 579 



284. Gastrula stage of newt (Hertwig) ..... 580 



285. Dissection of tadpole (Milnes Marshall and Bles) . . 581 



286. Life history of a frog (Brehm) . ..... 585 



287. Csecilian (Ichthyophis} with eggs (Sarasin) .... 588 



288. External appearance of tortoise ...... 593 



289. Carapace of tortoise ........ 594 



290. Internal view of skeleton of turtle ..... 595 



291. Dissection of Chelonian heart (Huxley) .... 595 



292. Heart and associated vessels of tortoise (Nuhn) . . . 596 



293. Lateral view of brain of Hatteria pttnctata (Osawa) . . 597 



294. Hatteria or Sphenodon (Hayek) ...... 598 



295. Side view of skull of Lacerta (W. K. Parker) . . . 601 



296. Heart and associated vessels of a lizard (Nuhn) . . . 603 



b 



