April 29, 1875J 



NATURE 



503 



the three species of Aster\ and Melanodendron are among 

 the woody Asteroid forms exemplified in the Antarctic- 

 American Chiliotrichium, in the Andine Diploslephiioit, 

 and in the Australasian O/raria. Pctrobium is one of 

 three genera, remains of a group probably of great anti- 

 quity, of which the two others are Podaiithus in Chili, and 

 Asteiitma in the Andes. The Psiadia is an endemic spe- 

 cies of a genus otherwise Mascarene or of Eastern Africa, 

 presenting a geographical connection analogous to that 

 of the St. Helena Melhanice of De CandoUe with the 

 Mascarene Trochetia." 



In many of the other constituents of the flora — Mcscin- 

 bryanthemtim. Pelargonium, Phylica, Lobelia, Wahlcn- 

 bergia, there is an obvious connection with the South 

 African flora. But the changes in the physical geography 

 of the Old World must have been very considerable, since 

 the Mascarene Archipelago and St. Helena received their 

 vegetation from any common source. 



Questions of this kind, which are the real matters of 

 interest about St. Helena from a biological point of view, 

 Mr. Melliss scarcely touches, or quite inadequately. 

 And this is the more tantalising, as so large a body of 

 undigested information has not hitherto been brought 

 together about any oceanic island. Here and there sig- 

 nificant facts of the same kind may be gleaned from the 

 lists of the fauna. Thus a beetle, Steiioscelis hylastoides, 

 WolL, appears to be peculiar to the Cape and to St. 

 Helena ; Buliinus helena, Quoy, is a Mascarene and 

 East African type ; while the great B. aiiiis-vulpina, 

 Chemn. (now, like the last, e.xtinct), belongs to a group 

 peculiar to Tropical America. 



Apart from these points, the mere history of the vicissi- 

 tudes which the animal and vegetable Ufa of the island 

 has gone through since the Portuguese first visited its 

 forest-covered but now denuded hills, forms a striking series 

 of episodes in the general struggle for existence. What 

 the goats forbore to browse, introduced j plants like the 

 blackberry strangled. It would seem as' if strenuousness 

 died away among assemblages of organisms^which had 

 established a modus viveiidi amongst themselves. Rude 

 impulses from without, when at last the isolation is broken, 

 achieve a comparatively easy victory. One cannot fail 

 noticing the uniformity of language with which this is 

 described, whether the invasion takes the shape of goats, 

 blackberries, white ants, measles, or even dissent, which, 

 " introduced by a Scotch Baptist minister about the year 

 1847, soon spread" (page 33). 



The fifty-six plates with which the volume is illustrated 

 deserve a word of notice. Thirty-one of these are effec- 

 tive illustrations of the plants from the drawings of Mrs. 

 Melliss, with dissections from those by Burchell in the 

 possession of Dr. Hooker. A large proportion of the 

 most curious of the St. Helena plants have been figured 

 by Dr. Hooker in the hones Plantiaum, but that is a 

 somewhat inaccessible publication, except to botanists, 

 and the present series of botanical plates really gives the 

 present work its chief interest. W. T. T. D. 



Heredity 



Heredity, a Psychological Study of its Phenomena, 

 Laws, Causes, and Consequences. From the French 

 of Th. Ribot. (Henry S. King and Co., 1875 ) 



IF M. Ribot intended this work to be regarded as an 

 original contribution to the philosophy of evolution, 

 is impossible to consider his efforts successful. He 



styles the book a " Psychological Study," and he shows 

 therein an intimate acquaintance with the writings of all 

 the principal authors who have created the new philo- 

 sophy. Darwin, Spencer, Bain, Gallon, Lucas, and some 

 others are constantly appealed to, or made to contribute 

 to his pages. M. Ribot has further collected from older 

 writers, and from medical works, a great number of facts, 

 often more curious than authentic, bearing upon the 

 question of heredity. He has composed a very readable 

 and interesting essay on the subject, of a semi-popular 

 character, and no doubt theie is plenty of room for such 

 a work, epitomising and presenting in a connected form 

 the great abundance of facts and generalisations already 

 accumulated upon this subject. But it is difficult to 

 regard the work as more than a compilation, and there 

 are several important deficiencies which may be pointed 

 out. 



I should have liked to meet in the book some clear and 

 consistent view as to what heredity really means, but M. 

 Ribot's ideas seem to waver. At the outset (p. i) he says : 

 " Heredity is that biological law by which all beings en- 

 dowed with life tend to repeat themselves in their descen- 

 dants. ... By it nature ever copies and imitates herself. 

 Ideally considered, heredity would simply be the repro- 

 duction of like by like." In many other passages he 

 repeats, no doubt correctly, that heredity is the generation 

 of like by like. Any feature in a living being which is 

 not found in any one of its ancestors cannot be called 

 hereditary. From similar conditions follow similar effects. 

 Thus, if heredity had been the sole influence moulding 

 living beings, we must_ all have had exactly the same 

 features and characters. 



In other passages M. Ribot takes^an opposite view, and 

 speaks of heredity as the cause of difference. In p. 387 

 he concludes that " heredity is really, therefore, partial 

 identity," and he adopts a solution of the question " which 

 attributes to heredity, a creative part." This view he 

 explains as follows (p. 34) : — " In the hypothesis of evo- 

 lution, heredity is really creative ; for since, without it, 

 it is impossible for any acquired modification to be trans- 

 mitted, the formation of instincts, properly so called, how- 

 ever slightly complex, would be impossible." Again, he 

 says (p. 344) : " If with the evolutionists we recognise in 

 heredity a force which not only preserves, but which also 

 creates by accumulation, then not only is the character 

 transmitted, but it is the work of fate, made up bit by 

 bit, by the slow and unconscious but ever accumulating 

 toil of generations." In pp. 302-3 he distinctly speaks of 

 heredity as an indirect cause of dechne, acting by way of 

 accumulation. A few pages later (p. 306) we are informed 

 that the first consequence of heredity is to render possible 

 the acquisition of new instincts. Surely there is a con- 

 fusion of ideas in these statements. 



As M. Ribot in other places fully explains, the condi- 

 tions governing the form and character of a living being 

 may be classed under three heads: (i) Heredity, by 

 which we mean the transmission of like characters from 

 parent to offspring ; (2) The influence of surrounding 

 objects— the environment, as Spencer calls it ; (3) Spon- 

 taneity, by which some writers have denoted the inexpli- 

 cable variation of the oftspring from the type of their 

 ancestors. Two meanings, however, may be attributed 

 to spontaneity : it may mean causeless variation, change 



