88 NATURAL SCIENCE. ^,^,^. 



these altered conditions, but they make every effort to get right side 

 out again ; if this is impossible, a new formation of ectoderm takes 

 place around the base of the tentacles, and may spread further over 

 the animal. There seems no reason to believe that the endoderm 

 ever functions as the ectoderm, or vice versa, while the stories about 

 the reproduction of Hydra from small parts have also been 

 exaggerated.^ 



Hence, though it is very sad to have to part with two such old 

 friends as the reversible Hydra and the resuscitated Rotifer, biology 

 will gain more than it will lose by this substitution of common sense 

 for paradox and puzzle. 



Extinct Vertebrata in the Grecian Archipelago. 



In a special chapter of a work on the natural productions of 

 SamoSj^Dr. Forsyth Major gives us further information on the wonder- 

 ful extinct vertebrate fauna of that island which he himself has been 

 the means of bringing to light. We are first told how the author 

 was led to believe in the existence of such remains from passages 

 occurring in the writings of Euphorion and Plutarch, and how he was 

 finally rewarded by their discovery near the village of Mitylene. Dr. 

 Major has determined the existence of over forty species of animals 

 from these deposits, of which all but four are mammals. Many of 

 these are common to the equivalent deposits of Pikermi in Attica, 

 Baltavar in Hungary, and Maragha in Persia ; and the relationship 

 of the fauna to that of modern Africa is exemplified by the number of 

 species of antelopes, by the occurrence of Ethiopian types of hyaenas 

 and rhinoceroses, and likewise by the occurrence of an ostrich and an 

 aard-vark. 



The most interesting of all the animals noticed by Dr. Major are 

 those of which the teeth were originally described as referable to an 

 ungulate {Chalicothevinvi), and the claws as those of an edentate. It 

 is concluded that, although these animals present a most remarkable 

 resemblance to some of the Odd-toed or Perissodactyle Ungulates in 

 the structure of their teeth and limbs, yet that they have really no 

 direct relationship, but represent a distinct order — Ancylopoda. The 

 three-toed feet, with their enormous curved claws, differ from those 

 of the Perissodactyles in that the middle toe is smaller than the 

 others; while in their powers of prehension these limbs are, of course, 

 quite unlike those of all modern Ungulates. Dr. Major considers 

 that while the representative of these animals found at Samos and 



1 For the latest literature on this subject, see Engelmann, Zool. Anzeiger, vol. i., 

 pp. 77-8 (1878); W. Marshall, Zeitschr. fi'iy Wiss. Zool., \o\. xxxvii., pp. 664-702, 

 and especially p. 682 (18S2). For an account of the experiments by Mitsikuri and 

 others, see American Naturalist, vol. xxi., pp. 387-8 and 773 (1887). 



" Samos. — Etude geologique, paleontologique, ct botanique, by C. de Stefani, C. J. 

 Forsyth Major, and W. Barbery. Lausanne, 1892. ato. 



