Page:The Scientific Monthly vol. 3.djvu/612

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6o6 THE SCIENTIFIC MONTHLY

recovered a whole series of these archaic fish types as they lived togetiier in the fresh water or the brackish pools of Upper Devonian time. (Fig. 14.)

In this period the paleogeographorf (Schm-hert) obtain their first evidence of the evolution of the terrestrial environment in the indica-

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� ��FiQ. 14. PiBii TiPKS OP Ttie Old Rxd Sindbtonb or Scotlikq. TTfpbk Devon- ian TtUE. Pbimit[VC Canoidb lOtSeolepit. ChrlrDlrpl*). prlmltlTC nplne-flniied sharks. Ac>DtbodlallB<DlpI<]oiinrAi»>.bottaiD-llTlnKOBtraFoderma (/■lerlcAIhva), flrst InQKQshM (DiplrriMl.parll}' nrmorpd GhdoIcIb fHoJoplychiui). 1, OtteoUpit, prlmlttve lobe-flnned Ganoid. 2. lloloplurhiui , Irluge -fluopd Caaold. 3. 6. CKeiracanttiM , spine. Sun ed shark (AcaalhodlaD). 4. Uipiacanttiu* , splDe-llatiFd shark (Acanthodlan). S, Cocco»tm* prlmlUre Arthrodlnn. 7. CheiroUpit. prlmltlTe Ganoid. S. S. Dlptens, primitive lung Bab. 10, Plerichthyi, botlom-llTlng OslrncodFrm allied to BothriottfU. Models Id the American Museuni or Natural IIIatorT. rratoratlons bT D«an. Huasakot and Horter, pnrlljr ntler Traqualr.

tions of the existence of parallel mountain ranpes on the British Isles, of active volcanoes in the Gasp6 region of New Brunswick, in the mountain formations of South Africa, and in the depressions of the center of the Enrasiatic continent into the great central Mediterranean sea, the Tethys of Suess. In the seas of this time as compared with Camlirian seas we observe that the trilohites are in a degenerate phase, the brachiopods are relatively less numerous, the echinoderms are rep- resented by the bottom-living starfishes, the sharks are abundant, the Ar- throdiran fishes are still abundant in Germany.

It was long believed that the Amphibia evolved from the Dipnoi, the air-breathing fishes of the inland fresh waters, and this hypothesis was .stoutly maintained by Carl Gegenbaur, who upheld what he termed

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