178 



NATURE 



[April 27, 19 16 



tion to see anticipations which are not strictly 

 legitimate. He points out that the Vais'esilca 

 theory of motion made only a distant approach to 

 Newton's first law of motion,, and that whilst a 

 good foundation was laid for the explanation of 

 the accelerated motion of falling bodies, Galileo's 

 discovery was not anticipated. But there would 

 seem reason to believe that Vachaspati laid the 

 foundations of solid geometry eight centuries 

 before Descartes, and that Bhaskara (1150 a.d.), 

 in computing planetary motion, appears to have 

 used the differential calculus. 



Ancient ideas on acoustics have a remarkable 

 similarity to modern theories. It was recognised 

 that the air was the physical basis of audible 

 sound, and that its propagation was to be con- 

 ceived on the analogy of waves in water. Various 

 views, however, seem to have been held concern- 

 ing the precise nature of the air-waves, as to the 

 character of the vibratory movement, and how the 

 molecules of a vibrating bell communicate their 

 motion to the contiguous air-molecules. Echo was 

 supposed to be a reflection of sound as an image 

 in a mirror is a reflection of light. Attempts were 

 made to explain pitch, intensity, and timbre by 

 differences in the characteristics of the air-waves. 

 The nature of musical sounds and intervals was 

 the subject of acute speculation. Medieval com- 

 pilations explain musical tones and their relations 

 with reference to melody, as harmony was alto- 

 gether unknown. 



The wonderful plant-life of India naturally 

 stimulated attempts at classification, and a short 

 account of the various systems attributed to 

 Charaka, Prssastapada, Amara, and others is in- 

 cluded in chapter iv. A section is devoted to 

 elementary ideas of plant physiology, character- 

 istics of plant-life, sexuality, and consciousness. It 

 is a curious and suggestive chapter, not without 

 interest to the modern plant-physiologist. 



Not less interesting are the early Hindu at- 

 tempts at the classification of animals based upon 

 mode of origin — whether placental, oviparous, 

 from moisture and heat, or from vegetable organ- 

 isms. Snakes naturally received much attention, 

 and elaborate accounts are given of the action of 

 the poison of the several venomous families. This 

 is one of the longest chapters in the book, and 

 the accounts of the various systems are given in 

 considerable detail. 



Space precludes any attempt to give any de- 

 scription of ancient Hindu ideas concerning physi- 

 ology and biology. Naturally, the phenomena of 

 metabolism, of the circulatory system, and of tlie 

 vascular and nervous system ; of the seat of con- 

 sciousness ; of foetal development ; sex ; heredity, 

 received attention, and were the subject of specu- 

 lation, often based upon acute and accurate 

 observation, always interesting, and frequently 

 highly suggestive. But enough has been stated to 

 show that Dr. Brajendranath Seal has given us a 

 most valuable contribution to the history of 

 science by means of a work which must have 

 involved a vast amount of study and research into 

 a literature which is oractically inaccessible to 

 European students of physical science. 



BRITISH FRESH-WATER RHIZOPODS. 



The British Fresh-water Rhizopoda and Heliozoc 

 By j. Cash and G. H. Wailes. Vol. ii 

 Rhizopoda. Part iii. By G. H. Wailes. Pj 

 xxiv + 156 + plates xxxiii + lvii. (London: Ra 

 Society, 1915.) Price I2:.'. 6d. net. 



TO say that the volume before us equals, 

 it does not surpass, its predecessors, n( 

 only in scientific value but in general constru( 

 tion, is to award it the highest praise. With th 

 completion of their task by the publication of th 

 concluding volume it will not be too much t 

 state that what Leidy has done for the fresl 

 water Rhizopoda of North America the authoi 

 of this work will have done for the group i 

 Great Britain. Since the publication of th 

 second volume (in 1908) the senior author, Jamf 

 Cash, has died, and a sympathetic biograph 

 forms a fitting introduction to this volume froi 

 the hand of Mr. John Hopkinson, who, as is we 

 known, rendered him material assistance in th 

 preparation of vol. ii., and to whom the preser 

 instalment is indebted for a series of synonymic 

 which may well serve as a pattern for all systen 

 atists, and may be said to constitute a practic 

 ally complete bibliography of the subject. 



The volume furnishes a very extended additio 

 to our knowledge of the distribution of thes 

 organisms in the British Isles, esp>ecially by th 

 incorporation of the splendid results of th 

 labours of Mr. G. H. Wailes (which were en 

 bodied in his monograph of the group publishe 

 in the reports of the Clare Island Survey), whi 

 now joins Mr. Hopkinson as one of the author 

 of this book. By the addition to the British 

 of Paulinella and Clypeolina, and the represei 

 tion of Gromia by Allogromia and Rhync 

 gromia, the number of fresh-water Rhizopi 

 recorded as British is raised from forty-seven 

 fifty. The confused species Euglypha alveol 

 is divided into E. acanthophora and E. tuber 

 lata, a simplification which will be welcomed 

 students of the group, supported as it is b\ 

 remarkable synonymy comprising no fewer tl 

 157 well-considered references. 



The authors direct attention to the special; 

 method of collecting reserve scales by E. crista 

 and the contrivance by which the ap>ex of the trt 

 is closed in E. tnucronata. The new classificat 1 

 of the Gromiinai will appeal as much to studc 

 of the marine as of the fresh-water Rhizopc 

 In this section the preoccupied name Pamphajs 

 is replaced by Lecythium, as the outcome o^a 

 laborious study of the existing synonymies. ^ 

 do not agree with Rhumbler (who is followed? 

 the authors) that Dujardin failed to notice '^ 

 anastomosing reticulations of the pseudopodia" 

 Gromia oviformis; his four papers publisheciD 

 1835 (Ann. Sci. Nat., 1835, " Infusoires," i^?) 

 make the contrary view clear, but for taxonornal 

 purposes Rhumbler 's sub-family, Allogromia jS 

 undoubtedly useful. An interesting accoun'''' 

 given of the reproductive processes of M' ''" 

 gromia socialis, as also of the indifferently ma'"' 

 or fresh-water genera, Lieberkuehnia and R-'' 



