November 29, 1X04] 



NA TURE 



99 



thrown one way or another by the men. The three-inch 

 tube for setting the slide-bars cannot be trusted for 

 accurate work, owing mainly to the end drooping by its 

 own weight, and slackness in the glands and temporary 

 front cylinder cover. .Squaring over the frames is nowdone 

 by a long square, one arm being placed through the driving 

 horns, and held against them. The distance is then 

 measured from the leading and trailing horns to the 

 other arm of the square when held in the four positions. 

 If the frames are square, these measurements should 

 agree, if the horns are similar throughout. A woven 

 silk cord is best for lining up the frames and cylinders. 



The volume concludes with a lengthy description of 

 the Joy valve gear, a gear not generally used in loco- 

 motive work. It is a pity the author does not treat the 

 so-called .Stephenson link motion in a similar exhaustive 

 manner. In conclusion, we must congratulate the author 

 on having written the first readable and accurate book 

 on the construction of the locomotive engine. He has 

 treated his subject in a masterly way ; he describes, as a 

 rule, the most recent practice in a thoroughly professional 

 manner. The work is well and copiously illustrated, and 

 will be of great use to those who take an interest, either 

 professionally or in an amateur way, in the construction 

 of the locomotive. N. J. LoCKYER. 



INDO-MALAYAN SPIDERS. 

 Malaysian Spiders. By Thos. and M. E. Workman. 

 Parts I, 2, and 3. (Belfast : Published by the Authors, 

 1S94.) 



THE material upon which this work is based was 

 obtained by the authors during a recent visit to 

 the East Indies ; and since the entire collection has 

 been submitted for e.\amination and description to Dr. 

 Thorell, who has made a special study of the Arachnida 

 of this quarter of the globe, it may be taken for granted 

 that the species have been as satisfactorily identified as 

 is possible. Most of them, whether old or new, have 

 been already described in detail by this specialist. But 

 his systematic zoological work, although in its way of 

 unrivalled excellence, is open to two objections. We 

 have, in fact, heard it alleged, firstly, that the span of 

 human life is too short, and the number of existing 

 spiders too great, to admit of deserving attention being 

 paid to his exhaustive descriptions ; and, secondly, that a 

 deal of vexatious trouble and valuable time might be 

 saved by the addition of a few figures to the overwhelm- 

 ing amount of text. It is evident that Mr. and :\Irs. 

 Workman have realised the full force of these two objec- 

 tions ; for this book of theirs may be briefly described as 

 a supplement designed to make good the defects in Dr. 

 Thorell's report upon their collection. 



The work is being issued at intervals in shilling parts, 

 of which three, comprising in all twenty-nine plates, have 

 up to the present time appeared. Every species is 

 illustrated by a hand- coloured figure, together with out- 

 line sketches of structural details ; and accompanying 

 each set of figures is an explanatory page of text, giving 

 the name and synonymy, the affinities and distribution 

 of the species, and some measurements of the type- 

 specimen. Moreover, in some instances interesting 

 items of news respecting habits, &c., are added ; and in 

 the case of the orb-weavers, a figure of the web charac- 

 NO. 1309, VOL. 51] 



teristic of the species is engraved on a separate plate. 

 It is this part of the work, we feel sure, that w ill prove of 

 the greatest interest to the student of spider-life. Even 

 the pure systematist may learn from it valuable facts 

 bearing upon his aspect of the subject. For the figures 

 and descriptions of the webs afford indisputable evidence 

 that remotely allied genera may construct snares of 

 substantially the same kind, as may be seen by a com- 

 parison of the nests of Callinethis, Gea, Argyroepeira, 

 Epeira, and Gaslracantha, represented in parts I and 3 ; 

 and that within the limits of the same genus, species may 

 be found that spin webs differing widely in important 

 points of structure, as a glance at the figures of the webs 

 of Epeira calyptrata, iinicolor, and heccarii, in parts i 

 and 3, will show. Clearly the importance of these facts 

 must be steadily kept in view by those who base their 

 classification of spiders on the structure of the webs. 



The discovery of the snare of Uloborus qiiadri-tuber- 

 culatiis has given rise to a curious problem. This web 

 is always spun on the pine-apple, and is of a peculiar 

 basket-shape, the peculiarity consisting in the remark- 

 able adjustment that is exhibited between the structure 

 of the web and that of the plant. But the pine-apple is 

 a native of South America, and has only of late years 

 been introduced into Singapore ; so that if the spider is 

 truly a native of the latter place, it has evidently rapidly 

 modified its spinning instincts in response to the slight 

 change in its environment brought about by the introduc- 

 tion of the pine-apple. Before such a conclusion, how- 

 ever, can be looked upon as an established fact, evidence 

 must be produced that the spider and the plant were not 

 concomitantly brought from the Neotropical to the 

 Oriental region. 



Another very interesting fact is noticed in connection 

 with Argyroepeira striata. We are told that this spider, 

 which is normally of a bright golden tint, " has the power 

 j of darkening down its brilliant colouring when fright- 

 i ened.'' (part 3, p. 19.) The importance of this obser- 

 vation is greatly enhanced by the independent discovery 

 made by Mr. H. H. J. Bell, and published in X-\ture 

 (vol. xlvii. p. 558), to the effect that a West African 

 species of Argiope possesses the same faculty of rapidly 

 varying its colour under the stimulus of changing sur- 

 roundings. 



From what has now been said, it may be judged that 

 the value of this book, as an addition to the literature 

 of spiders, is both great and unquestionable. But it is 

 impossible to shut one's eyes to the fact that its general 

 excellence is slightly marred by a few blemishes, which, 

 at the risk of appearing ungrateful, we think it our duty 

 to point out ; not, be it understood, with the object of 

 fault-finding, but in the hope that none of them may be 

 copied by other authors, and that some, at least, may 

 not reappear in succeeding parts of the work. 



In the first place, respecting the method of publica- 

 tion, it is a pity that both preface and introduction have 

 been altogether omitted, and that species belonging to 

 such widely different families as Oxyopida:, Attida, 

 Thomisidce, and Epeiridcc, should be indiscriminately 

 mixed, as they have been in part i. With regard to 

 the preface, we hope that the authors will see the appli- 

 cation of the maxim, "Better late than never"; and 

 although the adage, " What is done cannot be undone," 



