102 Bihliograpliical Notices. 



We are surprised at the summary manner in which the view that 

 spiders attach stones &c. to their webs as so-called counterpoises, 

 is rejected. Dr. McCook is perfectly right to sift as carefully as he 

 has done the evidence for or against the belief; but it is question- 

 able whether he is correct in deciding that the attachment of such 

 a weight would be harmful. Why so ? A web blown by the wind 

 would surely be more easily destroyed if all its points were attached 

 to fixed objects, than if one or more strands were fastened to, e. g., 

 a pebble lying on the ground, which would " give," so to speak, 

 when pidlcd bj' the strands under stress of the wind. Where some- 

 thing must " give," it is surely better for the spider that it should 

 be the pebble than the web. 



In Chap. xvi. of vol. i. Dr. McCook discusses at some length the 

 question of spider venom. He starts with the assumption that the 

 fluid secreted in the mandibles and ejected at the apex of the fang is 

 poisonous. He then proceeds to show that it is perfectly harmless. 

 Numerous cases are cited in suj^port of this, Lucas even having been 

 bitten by Latrodectus and 8imon by the historical Tarantula without 

 suffering harm. It is true that the universal testimony with regard 

 to Latrodectus far outweighs almost any amount of negative evi- 

 dence ; and the conclusion that Dr. McCook finally comes to is 

 that the poison is a sparingly used reserve weapon. This may be 

 the case of course ; but the explanation is not altogether satis- 

 factory, for it is apparently the only one that can possibly be put 

 forward if we assume the existence of a poison apparatus. Eut 

 what evidence is there for the assumption ? Certainly very little. 

 Why may not the fluid be merely secreted for digestive purposes, 

 such as, e. (/., for softening the tissues of the prey ? To make a 

 general statement with regard to all spiders from the particular case 

 of Latrodectus is not jiistifiable. It may well be that in this genus 

 the digestive fluid is harmful to man, while in all other spiders it is 

 not. Indeed this seems to us to be the obvious conclusion from 

 the facts at hand. With respect to the Thera])hosida), as Dr. 

 McCook himself suggests, it may well be that the fluid that is in- 

 jected into a wound causes inflammation from its very amount. 



The second volume is much more varied in its subject-matter 

 than the first. Thus Part i. is devoted to Courtship and Mating; 

 Part ii. to Maternal Industry and Instincts ; Part iii. to Early Life 

 and Distribution of the Species ; Part iv. to Sexes and their relation 

 to Habit ; Part v. to Hostile Agents and their Influence ; and 

 Part vi. to Fossil Spiders. Prequent reference is made to groups 

 which do not belong to the Orbitelarioe ; Avhile the section devoted 

 to Fossil Spiders seems wholly out of place. 



Clearly a considerable amount of the work of this volume has been 

 robbed of its novelty by the prior publication on the part of the 

 Peckhams of their articles on Sexual Selection, Protective Ilesem- 

 blances, and Mental Powers in Spiders. One or two points, however, 

 may be noticed. 



Commenting on the difference in the behaviour of a Tarantula 

 and an Ejieira when experimented on with a vibrating tuuing-fork 



