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NATURE 



\yuly i\, 1879 



them directly from Phoenicia, as Benfey wished to do, 

 or from the Himyaritic characters of Yemen as Lenor- 

 mant alleges. The traditional belief of the Hindus that 

 their ancient literature was handed down by oral recita- 

 tion alone is thus confirmed, and a remarkable illustration 

 afforded of the powers of a trained memory. The famous 

 maxim that a literature cannot exist without writing must 

 be given up, and the rigid sceptics who refuse to admit 

 that any historical truth can be extracted from oral tradi- 

 tion lose their most formidable argument. 



The earliest material used for writing purposes in India 

 seems to have been the bark of the Nturja, which is 

 usually identified with the birch. It is worth notice that 

 our own word boo/c has the same origin as beech, and testi- 

 fies to a similar employment of the bark of the beech-tree 

 among our Teutonic ancestors. It is probable, however, 

 that the characters of our first " books " were cut upon 

 the soft wood or bark of the beech in the form of runes, 

 and not painted as in the case of the birch books of 

 ancient India. Nevertheless we must not forget that 

 Venantius Fortunatus when alluding to the runes in the 

 seventh century speaks of them as being "painted" on 

 tablets of ash. A. H. Sayce 



OUR. BOOK SHELF 



Parasites ; a Treatise on the Eniozoa of Man and Ani- 

 mals, including sotne Account of the Ectozoa. By 

 T. Spencer Cobbold, M.D., F.R.S., F.L.S. (London: 

 J. and A. Churchill, 1879.) 



There are several groups of animals which from time im- 

 memorial have been more or less generally neglected by 

 zoologists, and which have induced but very few amongst 

 the latter to make a specialty of their investigation. As 

 an instance of comparatively highly developed animals to 

 which this remark applies, we need only point to the whole 

 class of cephalopoda, and among the lower animals the 

 entozoa are certainly a good case in point. Apart from 

 the comparative scantiness of the literature treating of 

 these animals, it has the additional disadvantage, in 

 common with much other zoological literature, of being 

 scattered in the numerous volumes of several hundred 

 different scientific serials. Dr. Cobbold has for a long 

 time been held an eminent authority on helminthology, 

 and, as he states in his preface, many hundreds of cor- 

 respondents, not having ready access to the works of 

 Rudolphi, Diesing, and Dujardin (three great foreign 

 authorities on the subject), have applied to him for iden- 

 tification of parasites they met with in dissections or 

 otherwise. He therefore pronounces the most justified 

 hope that by the work now published a reasonable limit 

 may be placed upon the number of future applicants. 

 What particularly characterises Dr. Cobbold' s work is 

 the thoroughly scientific enthusiasm with which it is 

 written, and which in itself is admirable. We cannot 

 help reproducing the closing sentences of the preface, 

 which will give to our readers a true notion of the spirit 

 to which, according to our view, a scientific work ought to 

 owe its origin : — 



" The study of the structure and economy of a humble 

 parasite brings to the investigator no slight insight into 

 the workings of nature. If these workings cannot at all 

 times be pronounced to be 'good and beautiful,' they 

 must at least be characterised as ' true.' The knowledge of 

 the true — especially if that knowledge by its practical appli- 

 cations be calculated to confer substantial benefits upon 

 man and his inferior fellow-creatures — ought to be held in 

 high esteem ; but apart from this purely utilitarian view, 

 there remains for the investigator the dehght occasioned 

 by the inrush of new scientific ideas. The average mind. 



being either essentially commercial or ridiculously senti- 

 mental, as the case may be, is totally incapable of com- 

 prehending the motive power that animates and guides 

 the votary of science. The late Prof. Faraday, a man 

 wholly untinged by the ambitions of Wealth and power, 

 once remarked to me that there were no people so difficult 

 to instruct as those who were ignorant of their own 

 ignorance. It is just these very persons who, when 

 placed in high positions of social, political, or professional 

 trust, most powerfully contribute to check a nation's 

 progress. There are too few genuine workers at science 

 in this country. As one of the rank and file I claim only 

 to have honestly contributed my mite. I should like to 

 see a small army of helminthologists rise up and lay siege 

 to the fortresses at present securely held by thousands of 

 death-dealing parasites." None but an honest and true 

 worker will write such sentences as these; every well- 

 meaning man of science must concur with Dr. Cobbold 

 in the ideas he thus forcibly expresses. Upon an array 

 of workers of Dr. Cobbold's stamp a nation may justly 

 look with pride. 



Turning now to the book itself we need hardly say that 

 the author has executed the task he set himself in a most 

 praiseworthy manner. Apart from a voluminous contri- 

 bution of original work, he has consulted an almost in- 

 terminable list of bibliographies on the various kinds of 

 parasites, a work which in itself involved stupendous 

 labour. 



The contents are divided into two large groups, the para- 

 sites of man occupying the first division, and those of ani- 

 mals the second. Each division is subdivided into several 

 sections, and thus in the first we have descriptions in one 

 section of Trematoda or flukes, in the other those of 

 Cestoda or tapeworms, in the third those of Nematoda 

 or round- and thread-worms, and in the last those of 

 Acantocephala (thorn-headed worms), Suctoria (leeches), 

 and the parasitic foims of Arachnida, Crustacea, Insecta, 

 and Protozoa. In the second division the parasites of 

 animals are arranged according to the respective places 

 of their hosts in systenfatic zoology. The parasites of 

 Mammalia are subdivided according to the orders in 

 this class, beginning with Quadrumana and ending with 

 Marsupialiaand Cetacea. After this the parasites of birds, 

 reptiles, fishes, and invertebrate animals are considered 

 in due course. In relation to the parasites of man, the 

 author gives a great deal of valuable statistical information 

 which must be of special interest to the physician. 



Altogether we cannot speak too highly of Dr. Cobbold's 

 book, and congratulate the author warmly upon having 

 so efficiently filled a gap in zoological literature, the ex- 

 istence of which had long been felt by all working natu- 

 ralists and many medical men. 



A Contribution to Agricultural Botany. By A. S. 



Wilson. (Aberdeen : J. Rae Smith, 1879.) 

 The author of the small volume before us is alreadj- 

 favourably known as an investigator of more than one 

 obscure yet important problem connected with field- 

 botany. The text of his present discourse is "turnip- 

 singling." He approaches this subject in a characteris- 

 tically careful manner, taking into account, as he does, a 

 number of considerations which might easily escape the 

 attention of an ordinary observer or experimenter. The 

 object and manner of his experiments present no novelty ; 

 indeed, it seems to us that Mr. Wilson can hardly be 

 fully aware of the immense number of trials which have 

 been made, both in this country and on the Continent, in 

 order to ascertain the best distance apart for swedes and 

 turnips. However, experiments of this order certainly 

 require frequent repetition in order that the influence of 

 season, climate, soil, and manure, may be duly measured. 

 Any one of these conditions may so affect the result as to 

 invalidate a hasty conclusion drawn from one or two 

 years' trials, even when such trials have been conducted, 

 not in one locality, but in several. Mr. Wilson is quite 



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