July 15, 1880] 



NA TURE 



?39 



aim ; no biological conclusions are attempted nor struc- 

 tural details given, save such as appertain to generic or 

 specific diagnosis. Its value therefore is to the student 

 of the local fauna and the generaliser in the study of 

 geographical distribution. 



The work of course must be considered to a certain 

 extent as introductory only; many species will necessarily 

 be discovered and added to the fauna, whilst of those 

 described it is equally probable that some will prove of 

 synonymic value only. The last conjecture becomes 

 almost a certainty when an estimate is made of the diffi- 

 culties under which Prof. Berg must have worked, so far 

 removed from all the large collections, identifying or 

 separating frequently by the help of poor descriptions, 

 with the impossibility of examining the original types. 

 His descriptions however are very clear, and have as a 

 rule appended the differentia specifica from a nearly allied 

 form. It is much to be regretted that this course is not 

 more usually followed by some other entomologists, and 

 it would almost appear in many cases that from being so 

 frequently told by the biological philosopher that descrip- 

 tive is the lowest form of scientific work, that the 

 describers themselves in despair had done the work in 

 the very lowest manner. It was well said that " some see 

 differences and no resemblance, others resemblance and 

 no difference, whilst some again can see neither the one 

 nor the other," and thus the help acquired from com- 

 parative diagnosis appended to an exhaustive description 

 becomes the more necessary when it is not possible to 

 give a figure of the species. Whatever conception may 

 apply in the mind of the individual worker as to the much 

 vexed term "species," it is at least to be expected that 

 the limits of variation can only be estimated by one who 

 has thoroughly studied a group and knows some little of 

 their life histories. It is in this field that the specialist 

 should really be considered a prophet, and in entomology 

 there are not only families but even genera which are so 

 peculiar and unique in the variation of their species that 

 the variable might with advantage be added to the 

 structural diagnosis. In the Rhynchota this is extremely 

 applicable, even structural characters which are constant 

 and specific in one genus being variable and of no specific 

 value in another, whilst colour and size, generally of no 

 moment, are in some few instances beacons which denote 

 specific differentiation. 



In studying a work of this nature we become sensible 

 of the vast unexplored field of entomology. We here 

 possess the identifications and names of the forms consti- 

 tuting a fauna, but by what methods its homogeneity was 

 secured remains still to be discovered. Which species 

 or genera are even pleistocene forms which have been 

 introduced by man, or by other means of involuntary 

 migration, we have at present no record. The inter- 

 dependence on the botanical geography of the district 

 must always be a factor in the distribution of the non- 

 carnivorous forms of the RhjTichota, and the meteoro- 

 logical conditions of a country will in future be more 

 studied by entomologists who are investigating local 

 faunas. 



Prof. Berg has introduced a valuable addition to his 

 work in^ the descriptions, where possible, of immature 

 forms. LarvEe in this order are most difficult to ade- 

 quately describe, and we may hope that the author in 



some subsequent publication may be able to give us 

 illustrations of the same. 



W. L. Distant 



THE HUMAN VOICE 

 The Mechanism of the Human Voice. By Emil Behnke, 

 Lecturer on Vocal Physiology at the Tonic Sol-fa 

 College. (London : J. Curwen and Sons, 1880.) 



THE object of this little book is to give singers a plain 

 and comprehensible view of the musical instrument 

 on which they perform. The author seems to have suc- 

 ceeded in this attempt remarkably well. He has evidently 

 had much practical work himself, and has especially set 

 himself the task of examining the action of the vocal 

 organs during singing by means of the larj'ngoscope, and 

 his record of his own experience in acquiring the use of 

 that beautiful instrument is not only interesting but of 

 much practical value. The last section of the book is 

 devoted to the teachings of the laryngoscope, as to the 

 action of the vocal ligaments in producing voice, with 

 especial reference to the so-called registers. "A register 

 consists of a series of tones which are produced by the 

 same mechanism," is his definition (p. 71), which is new 

 and complete, and he proceeds to explain the different 

 mechanism of each kind of register as actually observed 

 on singers. There are some good remarks on breathing 

 (pp. 17-22). All information is given throughout in clear, 

 intelligible language, and illustrated by fourteen woodcuts 

 (not all original), which are purposely rather diagrammatic 

 in character, in order not to confuse the eye with too 

 many details at a time, but every essential point is gradu- 

 ally introduced. The author seems to have been diligent 

 in the consultation of authorities as well as in practical 

 work of his own, and the book may be safely recommended 

 to all singers, and others who are desirous of knowing 

 how vocal tones are produced. 



There are a few things which may be pointed out in the 

 hope that they will be corrected in a second edition, which 

 ought to be soon required. On p. 4 the author implies 

 that former musical pitch was a major to a minor third 

 flatter than at present. For all music now sung the 

 difference was scarcely more than a semitone. On p. 30, 

 and again on p. 70, he says : " The vocal ligaments, by 

 their vibrations, cut the stream of air passing between 

 them into regular waves." It is difficult to see how these 

 words convey, even metaphorically, a correct conception 

 of what happens. " To cut a stream into regular waves," 

 is not a very intelligible operation. The expression should 

 certainly be altered, and a few lines added to convey the 

 full notion. On p. 37 the author seems to be wrong in 

 considering that glottis (or "tongue" in the singular) refers 

 properly to the vocal ligaments (or " tongues " in the 

 plural). It is merely what he terms the " chink," or the 

 tongue-shaped space between the vocal ligaments as 

 shown in PI. X. A. He also omits to notice especially the 

 cartilaginous glottis between the pyramids (arytenoids), 

 although it appears in Plate X. c, and XIV., XV., XVI. 

 On p. 44 he gives as a function of the pockets (ventricles 

 of Morgagni) that " they allow the stream of air which 

 has just been converted into tone to expand sideways, 

 thereby materially adding to its resonance." The whole 

 phrase is confused and should be entirely re-written ; the 



