NA TURE 



[July 5, 1906 



The chapters deaHng with the theory of single 

 phase and polyphase meters is complete and satis- 

 factory. All the best known methods of measuring 

 alternate current power are described. A matter of 

 some importance is the effect of wave shape on the 

 accuracy of registration ; errors due to this cause 

 may amount to 5 per cent, or more with meters 

 of the induction motor type when running on non- 

 inductive load, while the same meters record quite 

 accurately when supplied with a sine wave of potential 

 difference. The chapter dealing with tariff meters 

 is full of useful information for the central station 

 ■engineer, and the subject is well treated. The Hop- 

 kinson doctrine (one might almost call it an axiom) 

 that " the charge for a service rendered should bear 

 some relation to the cost of rendering it " is funda- 

 mental, but one of the chief disadvantages in its 

 application in the Wright maximum demand systerri 

 is, as Mr. Solomon says, that " the average con- 

 sumer experiences considerable difficulty in under- 

 standing it, and the attitude of the consumer cannot 

 be ignored." 



Chapter .\i. gives a description of a large number 

 of pre-payment meters, and in the next chapter tariff 

 and hour meters are dealt with in the same way. In 

 the penultimate chapter some special mechanical 

 features in meter design are described, for the obvious 

 reason that " the proper working of a meter depends 

 on its mechanical as well as its electrical design." 

 The subject of meter testing is discussed at some 

 length in the last chapter. 



The book should be of great value both to students 

 and to central station engineers who wish to know 

 ■iomething about the instruments in use on their 

 supply systems. 



A NEW VOLUME OF THE "FAUNA OF 

 BRITISH INDIA." 

 Tlie Fauna of British India, including Ceylon atid 

 Burma. Published under the authority of the Sec- 

 retary of State for India in Council. Edited bv 

 Lieut. -Colonel C. T. Bingham. Rhynchota, vol. iii., 

 Heteroptera-Homoptera. By W. L. Distant. Pp. 

 .xiv-l-503; figs. 266. (London : Taylor and Francis; 

 1906.) 



THE present series of works was initiated and 

 carried on for upwards of twenty years under 

 the able editorship of the late Dr. VV. T. Blanford, 

 and as this is the first volume issued under the superr 

 vision of his successor, Lieut. -Colonel C. T. Bingham,, 

 this seems to be a fitting opportunity to summarise 

 the progress that has already been made. In Vertex 

 brates eight volumes have appeared — one on Mam- 

 malia, by W. T. Blanford; four on Birds, by Eugene 

 W. Oates and W. T. Blanford; two on Fishes, by 

 Francis Day; and one on Reptilia and Batrachia, by 

 (;. .\. Boulenger. In Invertebrates ten volumes have 

 appeared — one on Butterflies, by C. T. Bingham ; four 

 on Moths, by G. F. Hampson ; two on Hymenoptera, 

 by C. T. Bingham ; one (half-volume) on .-\rachnida, 

 by R. I. Pocock; and two on Rhynchota, by W. L. 

 Distant. 



NO I914, VOL. 74] 



Respecting future arrangements. Colonel Bingham 

 announces that four volumes on Beetles (including 

 a volume on Phytophaga, by M. Jacoby), a second 

 volume on Butterflies, by Colonel Bingham, and a 

 volume on Land Shells, by the late Dr. Blanford 

 and Colonel Godwin-.Austcn, are in preparation, of 

 which it is hoped that the volume on Butterflies and 

 a half-volume on Longicorn Beetles may be issued 

 during the current year. 



Turning from this highly satisfactory record of 

 progress to the volume before us, we find that it 

 concludes the suborder Heteroptera (the true Bugs), 

 with families 17 to 24, Anthocoridae, Polyctenidae, 

 Pelogonidse, Nepida;, Naucoridae, Belostomatida?, 

 NotonectidcB, and Corixidse, including collectively 

 sixty-two species ; and commences the suborder 

 Homoptera with the families Cicadida and Fulgoridae, 

 of which collectively 570 species arc described. There 

 still remain three families of Trimerous Homoptera 

 — Membracidae, Cercopidae, and Jassidse — to be dealt 

 with in a future volume, as well as the Dimera and 

 Monomera, comprising the families Psyllidae, 

 Aphidida?, .\leurodids and Coccida. With the excep- 

 tion of the Anthocoridae and the curious bat-parasite 

 Polyctenes lyrae, Waterh., the Heteroptera described 

 in this volume are all aquatic, including the curious 

 water-scorpions, water-boatmen, and the great Belo- 

 stoma indicum, Lep. and Serv., which attains a 

 length of three and a half inches, and is perhaps 

 the largest heteropterous insect found in India, 

 though some of the allied South .American species are 

 larger. 



Our British species of the suborder Homoptera, of 

 which the froghoppers may be taken as typical, are 

 all small insects, the largest, our only British repre- 

 sentative of the true Cicadidae {Cicadetta montana. 

 Scop.), a scarce and local insect, only measuring an 

 inch and a quarter across the wings. But many of 

 the Indian species of Cicadidse and Fulgoridae arc 

 much larger, the largest Indian Cicada, Pomponia 

 intermedia, Dist., measuring seven inches across the 

 wings. 



Although many species of Cicadidae are more or 

 less spotted, and more or less opaque towards the 

 base, yet the tegmina and wings are, in most in- 

 stances, almost entirely transparent. In a few- 

 species, however, they are opaque, and brightlv 

 coloured. But in the Fulgoridae, or Lantern-flies, 

 many of which are of considerable size, measuring 

 two or three inches in expanse, the wings are often 

 opaque, and varied with such bright colours that they 

 might easily be mistaken for butterflies or moths by 

 persons ignorant of entomology. Indeed, one species, 

 Aphana caja. Walk., has received its name from its 

 superficial resemblance to a tiger-moth. 



Many Fulgoridae exude a white waxy substance, 

 which is sometimes very abundant and conspicuous. 

 Others, such as the true Lantern-flies or Candle-flies, 

 are conspicuous both for their bright colours and for 

 the long projection on the head of many of the 

 species. Some have short wings, others verv long and 

 narrow ones. Mr. Distant's figures are without 

 colour, but they give a verv good idea of the wing- 



