REVIEWS 171 



be necessary, and that the author will take the opportunity of bringing the 

 treatment of the material abreast of modern requirements. 



H. G. Greenish. 



Die Termiten oder Weissen Ameisen. By K. Escherich. [Pp. 198, with 51 

 text figures and 1 coloured plate.] (Klinkhardt, Leipzig.) 



The author has made some observations, in Abyssinia, on the nest of Termer 

 bellicosus, and, finding that the literature of the subject is scattered through 

 numerous and often inaccessible periodicals, has compiled an excellent summary 

 of the life-history of termites, as far as this is known. The book provides an 

 admirable introduction to the subject, and should prevent much haphazard destruc- 

 tion and hasty generalisation by indicating what details should be noted, either for 

 confirmation of old theories or for extending our present knowledge, when the 

 inexperienced investigator attacks a termite nest. We may join in the author's 

 hope that it will arouse greater interest in the study of these insects, though 

 it may be doubted whether any real progress will be made until some method is 

 discovered whereby they can be observed under natural conditions. The coloured 

 plate — which shows the king and queen in the royal cell — illustrates this point : 

 considering the disturbance created in opening a termite hill, it can scarcely be 

 expected (although the author believes it is so) that the condition of affairs in 

 a royal cell removed from the nest is normal. The author figures the soldiers 

 guarding the king and queen, but it is extremely doubtful whether soldiers inhabit 

 a royal cell under normal conditions. 



The first chapter describes the various forms of workers, soldiers, and winged 

 insects, their development (after Grassi) and functions, and the probable causes of 

 their differentiation from larvae which are assumed to be identical in every respect : 

 on the last point, the theory of parasitic castration is favoured. The second 

 chapter deals, inter alia, with the formation of new colonies : this section is the 

 least convincing, since the methods described have been deduced from observa- 

 tions on species which form colonies consisting of a few individuals, and will not 

 hold good in the case of the mound-building species. 



Chapter III. describes the various forms of nests, and is the longest in the 

 book. On this head there is abundance of information available, more or less 

 correct, and the author has selected his examples and illustrations judiciously. 

 With slight alteration, Holmgren's classification of the types of termite nests is 

 followed, and they are divided, first, according to the arrangement of the 

 chambers, into "non-concentric" and "concentric" nests ; while the second group 

 is subdivided, according to the material used, into pure earth nests, mixed nests 

 consisting of earth and wood, and pure wood (Jwh carton) nests. This classifica- 

 tion is open to considerable objection, for the concentric arrangement of supposed 

 concentric nests is by no means always recognisable, and some of the layers 

 required on Holmgren's theory are certainly not present in the large mound nests. 

 It would seem preferable to attach more importance to the "comb" than to the 

 outer covering of the nest, and to divide the nests in the first instance into those 

 which do not contain combs (e.g. Calotermes) and those which do. The latter 

 group could then be subdivided into (a) nests with a single comb contained in a 

 cavity of earth or wood, (b) nests containing numerous combs in similar cavities, 

 and (t) nests of a single comb, the outer layer of which forms a continuous closed 

 surface. At present there seems to be too great a tendency to consider the combs 

 as a " fungus garden " only, regardless of the facts that the fungus culture is only 

 a secondary feature, and that the combs are really homologous with the hanging 



