June 8, 1882] 



NATURE 



123 



young shoots of the daisy. . . . Our ants may not per- 

 haps lay up food for the winter (like the harvesters), but 

 they do more, for they keep during six months the eggs 

 which will enable them to procure food during the 

 following summer, a case of prudence unexampled in the 

 animal kingdom." 



Only one chapter of the book is devoted to bees, and 

 one other to wasps. These, however, are very interesting, 

 as the following resume 1 will show : — 



Numerous observations went to prove "that bees do not 

 bring their friends to share any treasure they have dis- 

 covered so invariably as might be assumed from the state- 

 ments of previous writers ; " and also that in general 

 bees are rather stupid in finding their way to honey out of 

 rooms, &c. Their affection and sympathy is even less 

 developed than in ants, so that Sir John doubts "whether 

 they are in the least fond of one another." Their special 

 senses are much the same as those of ants, hearing being 

 to all appearance absent, while smell and sight are well 

 developed, the latter enabling the insects to distinguish 

 differences of colour on coloured surfaces. They prefer 

 blue. 



All these remarks apply to the experiments on wasps 

 no less than to those on bees, except that they are some- 

 what more clever in finding .their way, and show less 

 preference for certain colours. One individual wasp was 

 tamed, used to perch upon the hand, "apparently ex- 

 pecting to be fed," and even allowed herself to be stroked 

 without any appearance of alarm. 



We have now said as much as our space permits to 

 recommend this work to all who take an interest in one 

 of the most interesting branches of natural history. We 

 can only find two points on which to offer criticism. Over 

 a hundred pages are occupied with appendices, conveying 

 minute details of the observations and experiments men- 

 tioned in the previous part of the work. These details 

 appear to us unnecessary in a popular book, and we 

 think that the space filled by them might have been more 

 profitably devoted to a well compressed abstract of the 

 observations of other naturalists upon the psychology of 

 the hymenoptera. 



The second point, which seems to us fairly open to 

 criticism, is that concerning the author's views on the 

 philosophy of vision. He discusses the theories of vision 

 by simple and compound eyes of insects, and says, " The 

 prevailing opinion of entomologists now is that each facet 

 receives the impression of one pencil of rays ; so that, in 

 fact, the image formed by a compound eye is a sort of 

 mosaic," and proceeds to observe that this theory "pre- 

 sents great difficulties," because "those ants which have 

 very few facets must have an extremely imperfect vision,'' 

 and also because the ants have simple eyes as well as 

 compound, so that, according to the theory, the former 

 cast reversed images, and the latter direct— a considera- 

 tion which leads Sir John to remark, "that the same 

 animal should see some things directly, and others re- 

 versed, and yet obtain definite conceptions of the outer 

 world, would certainly be very remarkable." 



Now, as regards the first objection, the perfection or 

 imperfection of the vision would not necessarily be deter- 

 mined by the number of the facets any more than by 

 their size. If a given area or eye-space is throughout a 

 receptive surface, it need make no difference whether the 



area is composed of a few facets or of many ; the perfec- 

 tion or imperfection of the apparatus as an eye would in 

 either case depend on the distinctness or definition with 

 which a pencil of rays is admitted into each facet, whether 

 the pencil itself be wide or narrow. 



And, as regards the second objection, we can see no 

 real difficulty in supposing that the same animal should 

 with some of its eyes see direct images and with others 

 reversed images, without any confusion resulting to its 

 mental perceptions. Let us first consider the case of 

 reversed images. Sir John Lubbock says that we "see 

 everything really reversed, though long practice has given 

 us the right impression." But this statement is not 

 quite correct. We do not really see things reversed, 

 for the mind is not a perpendicular object in space 

 standing behind the retina in the manner that a photo- 

 grapher stands behind his camera. To the mind there 

 is no up or down in the retina, except in so far 

 as the retina is in relation to the external world, 

 and this relation can only be determined, not by sight, 

 but by touch. And if only this relation is constant, it can 

 make no difference to the mind whether the images are 

 direct, reversed, or thrown at any angle with reference 

 to the horizon ; in any case the correlation between sight 

 and touch would be equally easy to establish, and we 

 should always see things, not in the position in which 

 they are tht own upon the retina, but in that which they 

 occupy with reference to the retina. Thus it really requires 

 no more "practice" correctly to interpret inverted 

 images than it does similarly to interpret upright images, 

 and therefore the fact that some eyes of an ant are sup- 

 posed to throw direct images, while others are supposed 

 to throw reversed, is not any real objection to the theory 

 which Sir John Lubbock is considering. 



We give these criticisms as the only ones we have 

 found it possible to make, and heartily wish so interesting 

 a book the success which it deserves. 



George J. Romanes 



OUR BOOK SHELF 



The Great Giant Arithmos, a Most Elementary Arith- 

 metic. By Mary Steadman Aldis. (London : Mac- 

 millan, 188 1.) 



"There are still mothers who wish to retain some 

 portion of that influence which nature intended them to 

 have in the training of their children, and who refuse to 

 abandon it wholly either to the schoolmaster or the state. 

 To such as these this little book is offered as a help in 

 laying the foundations of one of the most important 

 branches of instruction." In fifty-eight chapters the tender 

 student is led pleasantly, clearly, and thoroughly, from 

 the very simplest notions which lie at the threshold of 

 arithmetic till he (or she), having solved many of the 

 giant's easy riddles, is in a very good position to find out 

 for himself some of the harder ones. We should say that 

 the child who has had this course carefully laid before it 

 will have had its interest maintained throughout with- 

 out flagging, for the mode of presenting the subject is such 

 as to excite attention without causing fatigue. The 

 lessons are all short, the questions pointed, and such as 

 to draw out what knowledge has been acquired. Very 

 little more is done than to explain the elementary opera- 

 tions of numeration, addition, subtraction, multiplication, 

 and division. Towards the close a glance is given at 

 some of the giant's more recondite mysteries, as of parts 



