0O4 



NATURE 



[April 25, 1895 



It should te explained that an ordinary swarm-cell in 

 the feeding stage is an elongated body tapering at one 

 end into a long cilium or lash, and more or less truncated 

 at the end with several short cilia, the so-called pseudo- 

 podia. Within the body of the cell is a nucleus and 

 several vacuoles. 



With regard to hybrids between the plasmodia of 

 different species, Mr. Lister is in accord with De Bary, 

 and doubts the accuracy of Mr. Massee's observations. 



-Another point of great interest is the very wide geo- 

 graphical distribution of most of the species ; and the 

 main characters, Mr. Lister states, are remarkably con- 

 stant in specimens gathered in all parts of the world. 

 Mr. Lister gives a number of instances in which speci- 

 mens obtained from Europe, India, and North and South 

 America are identical in the most minute microscopic 

 detail. But there are exceptions, in which individuals 

 of the same species from tropical and temperate regions 

 exhibit differences in form ; the tropical ones being of 

 more elegant growth. 



In his description of the sclerotium, or resting stage, 

 of the Plasmodia, Mr. Lister states that the sclerotium 

 of Badhamia ulricularis can be revived, after preser- 

 vation in a dry state for three years, by being placed in 

 water. He also gives the results of a number of in- 

 teresting experiments on the vitality of various other 

 Mycctozoa. Altogether Mr. Lister's "Introduction" is 

 most instructive, and his descriptions are so clear, that 

 this book should go far to popularise the study of these 

 organisms. The plates, which are collotype repro- 

 ductions of water-colour drawings, are very good, but 

 much of the beauty of the originals is lost in the process. 

 It is a pity that they were not reproduced in colour. .And 

 this leads one to ask why the coloured figures in Massee's 

 "Monograph" are not cited. It is true there are 

 references to the pages of that work, which would lead 

 one to the figures, if one knew of their existence. It is 

 disappointing, too, that the author has attempted no 

 review of the previously existing literature, and has not 

 even thought it necessary to devote two or three pages to 

 bibliography. These omissions are all the more sur- 

 prising when one considers the facilities the author 

 enjoyed in the prosecution of his studies. 



A NEW WORK ON DYEING. 

 La Pratique du Teinturier. By Jules Gar(;on. Two vols. 

 Pp. 148 and 391. (Paris: Gauthier-Villars et Fils, 

 1893 and 1894.) 



THE art of dyeing has in recent years developed 

 so rapidly — having been practically revolutionised 

 and to a large extent remodelled during the last thirty 

 years — that text-books and works of reference dealing 

 with the subject rapidly become defective. We are 

 therefore always glad to welcome any new work which, as 

 far as possible, epitomises the information up to date. 



The great energy and enterprise exhibited by the large 

 firms of colour manufacturers in such a marked degree, 

 has, moreover, a tendency to develop what may be 

 distinguished as the art of dyeing, more rapidly than the 

 handicraft. It is, therefore, pleasant to note that, as 

 an engineer, the author of the book under review fully 

 appreciates the importance of the manipulative and 



NO, 1330, VOU 51] 



mechanical side of the subject, and gives a lucid de- 

 scription of many of the recently introduced appliances. 

 The plan of the book ditTers somewhat from that 

 usually found in works on dyeing. There i?, for instance, 

 no description of the character and properties of the 

 textile fibres or of the colouring matters ; but the various 

 theories which have been put forward to account for 

 dyeing processes, although of necessity based on such 

 facts, are discussed at considerable length, .\gain, 

 chemistry, as expressed by symbols and equations, i^ 

 conspicuous by its absence ; but a lengthy chapter on 

 the elements of chromatics is introduced. However, as 

 the book is|as yet incomplete (a third volume being 

 in course of preparation), it is too early to definitely 

 consider these as omissions. 



Volume i. contains a very short and sketchy historical 

 introduction, followed by a few notes regarding the 

 relative advantage of the natural and artificial dye-stuffs. 

 A classification of the colouring matters— following the 

 usual lines — is then given, with some very general note' 

 with regard to the application of each class of colour- 

 to the various fibres. This section of the book might 

 certainly have been considerably extended with advan- 

 tage, since undue compression necessitates a too-free 

 generalisation and an inadequate explanation of the facts 

 For instance, it is not suflicient to state (p. 13) th.it the 

 acid used in dyeing with sulphonic acid colouring matter- 

 (always employed as salts) serves to liberate the fret 

 colour acid. This is really a very secondary action 

 requiring only a small fraction of the amount of aciil 

 used, the principal function of which is to prepare tht 

 wool for combination with the dye. 



The methods of dyeing linen, jute, China grass, feathers 

 &c., are also noticed, a useful bibliography on the dyeing 

 of feathers being introduced. This commendable feature 

 is also noticed in several other sections of the book. 



The second part of the first volume is concerned with 

 the actual processes of scouting, dyeing, and finishing 

 The space allotted to this is again very small ; the de- 

 scription of the bleaching of cotton and of wool occupy- 

 ing less than half a page. Some useful hints are, how- 

 ever, given with respect to the choice of dye-stuffs, the 

 storing, dissolving and examination of colours, the causes 

 of defects, &c. 



M. Gar(;on devotes consider.able attention to the ijues- 

 tion of the fastness of colours, and discusses the infiuence 

 in respect to this property, of the nature of the fibre and 

 the colouring matter employed, of the method of apply • 

 ing the colour, of the character of the light and the 

 atmospheric conditions. With regard to the relationship 

 between the chemical con-titution of the colourinj; 

 matter and its behaviour on exposure to light, it is noted 

 that although most members of any particular j,'roup 

 act in a similar manner, a slight difference in constitution 

 is sometimes sufficient to cause a great difference inJ 

 permanence ; thus, although most of the anthracene 

 colours are " fast," and all the triphenylmelhane deriva-i| 

 tives "fugitive," pallein is much more resistant than the 

 closely allied eosin dyes, and by simply sulphonating 

 indigotin, one of the most permanent dyes is changed 

 into a very fugitive colour. It may be added thai 

 derivatives of methyl anthracene appear to be com 

 paratively fugitive to light. 



