NA TURE 



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THURSDAY, JUNE 30, 1910. 



.4 TREATISE ON ANTS. 

 Anis : their Structure, Development, and Behaviour. 

 By Prof. W. M. Wheeler. Pp. XXV4-663. (New 

 York : Columbia University Press ; London : Mac- 

 millan and Co., Ltd., 1910.) Price 215. net. 



FROM the classic work of Huber to that of Forel 

 our knowledge of ant life made comparatively 

 little progress. Forel 's remarkable researches, how- 

 ever, gave it a great impetus, and since then the 

 students of this most fascinating department of 

 natural history have been numerous and their dis- 

 coveries most interesting. 



Prof. Wheeler, who shows a most generous desire 

 to do justice to other observers, and has himself 

 contributed much to our knowledge, gives a biblio- 

 graphy which occupies no fewer than seventy pages of 

 his work. 



The most comprehensive contributions, he says, 



" have been made by Forel and Emery, but important 

 work has been done by Adlerz, Ernest Andre, Bates, 

 Belt, Bethe, Brauns, von Buttel-Reepen, Ebrard, 

 Escherich, Goeldi, Heer, J. Huber, von Ihering, 

 Janet, Karawaiew, Lameere, Lespes, Lubbock, Mayr, 

 Moggridge, Reichenbach, Reuter, Rothney, Santschi, 

 and Sykes." 



Yet for many years there has been no comprehen- 

 sive treatise on the subject. Prof Wheeler, who 

 promises us also a systematic monograph which will 

 no doubt be most useful, has endeavoured, as he 

 tells us, 



" to appeal to several classes of readers — to the general 

 reader, who is always more or less interested in ants ; 

 to the zoologist, who cannot afford to ignore their 

 polymorphism or their symbiotic and parasitic relation- 

 ships ; to the entomologist, who should study the ants 

 if only for the purpose of modifying his views on the 

 limits of genera and species ; and to the comparative 

 psychologist, who is sure to find in them the 

 most intricate instincts and the closest approach to 

 intelligence among invertebrate animals." 



Chapter i. the author devotes to "Ants as Dominant 

 Insects," discussing their interest for man, the prob- 

 able causes of their dominance, the comparison of 

 human and ant societies, the analogy between the ant 

 colony and the cellular organism, the economic im- 

 portance of ants, and their great interest as objects 

 of biological study. 



He then proceeds to their external structure — the 

 segmentation of the body; the integument; the head, 

 thorax, and abdomen. In the third chapter he deals 

 with their internal structure — the alimentary tract; 

 the glandular system ; the reproductive organs and 

 poison apparatus ; the circulatory system and fat 

 body; the respiratory, and, lastly, the muscular, 

 system. 



The fourth chapter is also devoted to the internal 

 structure, and especially that of the nervous system 

 and sense organs. In chapter v. he takes up their 

 development — the care of the young; the egg, larva, 

 pupa, and perfect insect ; their length of life, and 

 resistance to noxious influences. Chapter vi. deals 

 with polymorphism, its extent and character; the 

 NO. 2122, VOL. 83] 



phylogenetic origin and development; Weissmann's, 

 Spencer's, and Emery's theories; the three aspects 

 of the problem — physiological, ethological, and 

 psychological ; and the explanation of the development 

 of the worker. 



The same subject is continued in chapter vi., and 

 especially the origin of the worker ; the relation of 

 instinct to polymorphism; the differentiation in 

 function as the precursor of differentiation in 

 structure. 



Chapter viii. deals with the history- of myrmecology 

 and the classification of ants ; ix. with their distribu- 

 tion ; X. with fossil ants ; xi. with habits ; xii. and xiii. 

 describe the various forms and structure of nests, 

 their characteristics, the method of construction, &c. ; 

 xiv. deals with the Ponerine ants, which the author 

 regards as unmistakably primitive, and the ancestors of 

 the higher and more developed groups ; xv. is devoted 

 to the driver and legionary ants ; xvi. to the harvest- 

 ing ants; xvii. to the relations between ants and 

 vascular plants ; xviii. to the fungus-growing ants ; 

 xix. to the relations of ants to aphides, scale insects, 

 tree hoppers, and caterpillars ; xx. to honey ants ; 

 xxi. and xxii. to ant guests and parasites, especially 

 beetles, flies, hymenoptera, diptera, mites, and 

 nematodes. 



Interesting as these chapters are, the next are even 

 more so. They deal with the extraordinary relations 

 existing between ants of different species ; compound 

 nests and mixed colonies ; ant parasites ; slave-making 

 ants ; degeneration as the result of dependence on 

 others — a lesson, as he justly points out, to our states- 

 men and electors. 



In chapter xxviii. the author comes to the sensa- 

 tions of ants, different tj'pes of behaviour, the senses 

 as a basis for study, touch, smell and taste, hearing 

 and vision. 



The ocelli, which occur in the earliest known 

 fossil insects, are supposed to give an indistinct visual 

 image of very near objects, but, as he says, this view 

 is not vet clearly established. 



In chapters xxix. and xxx.. Prof. Wheeler discusses* 

 the question of instinct, and concludes with five 

 appendices, on (a) methods of collecting, mounting, 

 and studying ants ; (b) key to the subfamilies, genera, 

 and subgenera of the North American Formicidae, for 

 the identification of the workers ; (c) a list of described 

 North American ants ; (d) methods of exterminating 

 noxious ants ; (e) literature. 



Any one of these chapters would afford ample 

 materials for review, but this would involve too g^eat 

 a claim on the space at my disposal. 



I will only say a few words on the concluding 

 chapters, in which Prof. Wheeler deals with the in- 

 stincts of ants (chapter xxix.) and their plastic be- 

 haviour (chapter xxx.). 



He accepts the old scholastic distinction between 

 "memory" and "recollection," one being used 



" in the sense of having ideas of absent objects, rather 

 than in the sense of behaving differently to present 

 objects because of past experience with them. The 

 dog shows clearly that he remembers his master in 

 the latter sense by displaying joy at the sight of him. 

 Can we be sure that he has remembered him in the 



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