92 



SCIENCE, 



[Vol. VI., No. 130. 



'neotenism' (persistence of embryonal forms) re- 

 cently observed among the Urodela find at least a 

 partial explanation in the artificial transformation of 

 the axolotl as here described: for it has been shown 

 that the tendency to continued development can be 

 suppressed by suitable influences ; and such influences 

 may make their appearance naturally, and involve a 

 persistence of the larval condition. 



The importance of this series of investigations on 

 the primitive transit of the vertebrates from the water 

 to the land has been already pointed out. It must 

 not be forgotten that the remarkable tenacity of life 

 of the amphibians is a capital element, both in such 

 natural transit and in the successful result of the 

 experiments described. With insects the case is 

 very different: their metamorphosis has in certain 

 cases been suspended, both naturally and experi- 

 mentally; but all attempts which we have made to 

 induce the reversion of an insect to a larval condition 

 have so far miscarried. 



HAS MAN A TAIL 



Has man a tail? It is a question under dispute. 

 Anatomists have failed to agree as to what consti- 

 tutes a true tail. A tail is generally understood to 

 be a distinct posterior prolongation of the body, con- 

 taining a greater or less number of vertebrae. This 

 at once excludes all the cases of a caudal appendix 

 of a fleshy character, such as are found among the 

 rarer abnormalities of human structure. Where does 

 the tail end in front? The comparative anatomist is 

 obliged to designate all the vertebrae behind the sa- 

 crum as caudal; so that we are led to the conclusion 

 that the four or five vertebrae of the human coccyx 

 constitute a true though not a protuberant tail. In 

 the embryo, however, during the second month of 

 gestation, the coccyx does form a distinct conical 

 projection, which properly answers to all the require- 

 ments of a true tail; so that there can be no question 

 that man has a genuine though rudimentary tail, — a 

 survival from his simian ancestors. 



But as man is descended from long-tailed animals, 

 we ought to find evidence in the human embryo of 

 additional vertebrae. Professor Hermann Fol of Ge- 

 neva has shown {Comptes rending, 1885) that this is 

 the case. He has found, that, besides the thirty-three 

 or thirty-four vertebrae which persist into adult life, 

 there are other temporary ones. In an embryo five 

 and six-tenths millimetres (about twenty-five days), 

 Fol found only thirty-two vertebrae: Prof. W. His 

 had found thirty-three vertebrae in an embryo a little 

 larger, — seven millimetres. This led Fol to suspect 

 that there might be a still further increase, although 

 in the adult there are only thirty-three or thirty-four 

 vertebrae. He examined two embryos of eight or 

 nine millimetres. One of them was divided into a 

 series of three hundred and twenty sections, and 

 every section was drawn with a camera lucida. Upon 

 counting up the series, it was found that there were 

 thirty-eight vertebrae. Comparison with other em- 

 bryos satisfied Fol that this condition was perfectly 



normal. With the exception of the last two, all the 

 caudal vertebrae had a blastema like their anterior 

 fellows. The last two segments were indicated only 

 by the perfectly distinct muscular segments (myo- 

 tomes). The extremity of the tail was formed solely 

 by the medullary tube, covered only by the skin. 

 The notochord extended almost to the end. The 

 terminal vertebrae have only an ephemeral existence. 

 In embryos of twelve millimetres (six weeks) the 

 thirty-sixth to tliirty-eighth vertebrae have fused into 

 a single mass. In embryos of nineteen millimetres 

 the last five vertebrae have apparently fused to make 

 the permanent thirty-fourth. C. S. M. 



ETHNOGRAPHY OF ANTARCTIC 

 AMERICA. 



No inhabited land is found within the antarctic 

 circle ; and the title which the learned * secretary- 

 general of the ethnographic institution ' of France 

 has given to his memoir may therefore seem not 

 strictly warranted. But, in the more general sense 

 in which ' arctic ' is applied to climate as synonymous 

 with ' wintry,' the epithet ' antarctic ' is sufliciently 

 appropriate to the only region of the southern hemi- 

 sphere in which the climate is severe enough to exert 

 a controlling effect on the habits and character of the 

 people. 



Two years ago a little group of Fuegians, compris- 

 ing four men, four women, and three children, were 

 brought to Paris, and placed, as so many anthropo- 

 logical exotics, in the ' Garden of acclimation.' There 

 they remained for several weeks, and were visited, 

 of course, by many men of science. M. de Lucy- 

 Fossarieu had already made a study of the tribes and 

 languages of California, and naturally did not neglect 

 the opportunity of examining the natives of this 

 more peculiar and less known region. He saw them 

 frequently, and gained much novel information, 

 which considerably modified the opinions previously 

 entertained respecting this people. He was led to 

 examine the works of earlier observers from the time 

 of Magellan to our own, and to gather from their 

 descriptions, combined with his own observations, a 

 view as complete as can now be attained of the eth- 

 nology of the southern extremity of our continent. 

 Such, it appears, was the origin of this memoir, for 

 which students of science are under great obligations 

 to the author. It displays in a marked degree the 

 qualities of clearness of statement, and accuracy of 

 deduction, which distinguish the works of the best 

 French investigators. A summary of its contents, 

 with some additions derived from personal observa- 

 tion of the country and the people, will serve to show 

 the importance of the conclusions which the latest 

 evidence tends to establish. 



The Kio Negro, a navigable stream of considerable 

 length, divides Patagonia proper from the territories 

 of the Argentine Kepublic. From this river to the 



Ethnographie de I'Amerique antarctique: Patagnnn, Arau- 

 caniens, Fuegiens. Par P. de Lucy-Fossabibu. Paris, 1884. 

 4°. 



