NATURE 



49 



THURSDAY, NOVEMBER i6, 1899. 



THE CAMBRIDGE NATURAL HISTORY. 



The Cambridge Natural History. "Insects. Part II." 

 By David Sharp. Pp. xii + 626. (London : Mac- 

 millan and Co., Ltd., 1899.) 



THE appearancie of the concluding part of Dr. 

 Sharp's treatise on Insects, after an interval of 

 nearly four years since that of its predecessor, is most 

 welcome to all readers who were led by the first part of 

 this work to recognise what a step in advance had been 

 taken in the treatment of the subject. 



The present volume has confirmed the opinions we 

 then expressed in these columns on Part i., and again we 

 must record our admiration for the knowledge and in- 

 dustry of the author, and for the attractive manner in 

 which he has set forth his results ; for wherever the 

 subject-matter allows, the whole work is most fascinating 

 readmg. 



As was pointed out in 1896, the chief feature of this 

 work is the extensive use made of modern researches, of 

 a kind not hitherto found in text-books. So far as insect 

 morphology is concerned, one or two other recent works 

 may challenge comparison with the present one, but we 

 know of none that attempts to bring forward so large a 

 bulk of unfamiliar particulars, which in a " natural 

 history" are appropriately of the first importance, about 

 the habits and life-histories of insects. But such topics 

 take space, and a complete history of insects on this 

 large scale can only be condensed, even into the 1 100 or 

 more pages of this treatise, either by general compression 

 or by the selection of topics for detailed treatment, to the 

 exclusion, so far as practicable, of others. Dr. Sharp 

 has preferred the latter plan, and has been remarkably 

 concise in dealing with such parts of his subject as are 

 familiar from other accessible text-books, which this work 

 may be said rather to supplement than to supersede. 



The treatment of certain portions, particularly of 

 Coleoptera and Lepidoptera, will perhaps come as a dis- 

 appointment to those students who do not bear in mind 

 the limitations of space that have hampered the author. 

 Preconceived notions of the relative importance of insect- 

 families are not easily got rid of, and it is something of 

 a shock to find, e.g.^ the CerambycidcC dismissed with less 

 than four, or the Tineid^e with three pages. It would 

 have been an advantage if the editors could have seen 

 their way to devote still more space to the subject, per- 

 haps by restricting Vol. v. to the insects alone. The 

 association with the Prototracheata and Myriapods, if 

 zoologically orthodox, is not of much practical value. 



We think, too, that the omission of certain obscure 

 families, except for a bare mention of their existence, 

 would have been a gain. However much symmetry 

 may require a notice of each of the many families of 

 insects (Dr. Sharp enumerates eighty-five in the Cole- 

 optera alone), such notice is not worth giving unless it can 

 be adequately done, and the accounts, for example, of 

 the Rutelin;t, /Egialitida;, or Apioceridae, to select at 

 random, serve no clearly useful purpose. 



The present volume deals with the Tubuliferous and 

 Aculeate Hymenoptera, the Coleoptfa, Lepidopterai 

 NO. 1568, VOL. 61] 



Diptera, Thysanoptera and Hemiptera. The Aphan- 

 iptera are treated as a sub-order of Diptera, and the 

 Strepsiptera and Anoplura are included provisionally 

 with Coleoptera and Hemiptera respectively. 



Of these orders, the Hymenoptera, which lend them- 

 selves admirably to treatment from a bionomical stand- 

 point, are dealt with in great fulness, the observations of 

 M. Fabre on habits being in particular constantly referred 

 to at length. No less than fifty-three pages are devoted 

 to the ants alone, and, among much that is interesting, 

 attention may be called to the accounts of the Dorylides, 

 of the associations of ants with other insects (chiefly 

 based on Father Wasmann's work, and again dealt with 

 under Coleoptera), and to Mr. Green's drawing, on 

 p. 147, of a worker of Oecophylla smaragdina using a 

 larva of the species as a kind of animated gum-bottle for 

 joining together the edges of leaves. 



In proportion to their numbers, Coleoptera are the 

 least interesting of insects. Their life-histories are very 

 little known, and with the exception of the singular 

 parasitism and hypermetamorphosis found in the Can- 

 tharidas and their allies, are singularly devoid of notice- 

 able peculiarities. It is not surprising, therefore, that 

 even Dr. Sharp's intimate knowledge of the Order has not 

 prevented him from being " gravelled for lack of matter,' 

 and that this chapter, overweighted as it is with many 

 families, is among the least readable in the work. With 

 the removal of Gyrinidae from the Hydradephaga, few 

 entomologists will be disposed to disagree ; but the 

 grouping of the Clavicorn and Serricorn series of 

 Coleoptera into a single aggregate, to be called Poly- 

 morpha, is of questionable value. The new series is 

 admittedly incapable of definition, except by the fact 

 that its components do not belong elsewhere ; and to 

 associate into a single congeries of forms such widely 

 different families as, for example, the Staphylinidae and 

 Buprestidas, is to abandon classification, so far as a 

 fourth of the Order is concerned. 



Dr. Sharp pays a good deal of attention to stridu- 

 lating organs throughout his work, and describes and 

 figures (we imagine, for the first time) a remarkable 

 modification of the hind legs of Passalid larvae into paws 

 which scratch a stridulating plate on the middle coxae. 

 It is hard to imagine why a larva that lives in rotten 

 wood should desire to stridulate, but the practice appears 

 to be common among the Lamellicorns. He does not 

 refer to, and perhaps is not acquainted with, the remark- 

 able asymmetrical structure, probably a sound-producing 

 organ, which Ribaga has described in the abdomen of 

 the bed-bug. 



Great advances have been made in recent years in the 

 study of Lepidoptera, chiefly with a view to obtaining 

 sound classificatory points ; and the chapter on these 

 insects is noteworthy for the completeness with which it 

 deals with lepidopterous structure and development, 

 especially of the mouth parts (in connection with which 

 attention may be called to the figure illustrating the 

 pupal mandibles of Micropteryx, first described by Dr. 

 Chapman in 1883) and of the wings, wing-scales, and 

 coloration. An interesting sense organ of unknown 

 function in the abdomen of Chrysiridia is here described 

 for the first time. More might have been said with ad- 

 vantage on Dr. Chapman's researches on lepidopterous 



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