NATURE 



241 



THURSDAY, APRIL 29, 1909. 



CEtilRAL-AWERlCA}^ ORTHOPTERA. 

 Biologia Centrali- Americana. Insecta. Orthoptera, 

 Vol. I., by Dr. Henri de Saussure, assisted by Dr. 

 Leo Zelintner and A. Pictet. The Forficulidse, by 

 Count de Bormans (1893-1899). Vol. H., the 

 Acridiids, by Prof. Lawrence Bruner [the Tettiginae, 

 by .Albert P. Morse] , and the Phasmidas, by Robert 

 Shelford (1900-1909). (London : Dulau and Co.) 



THE Orthoptera have been sadly neglected by 

 British entomologists, and the sound systems 

 of classification of the component families, which we 

 now possess, are due almost entirely to the researches 

 of Continental naturalists. It is therefore not sur- 

 prising, though perhaps a little galling to one's sense 

 of patriotism, to find that the study of Central 

 American Orthoptera in the Godman-Salvin collection 

 was entrusted to French, Swiss, Austrian, and 

 American entomologists. The result of their combined 

 labours is a magnificent memoir on a most interesting 

 order of insects from one of the most interesting 

 regions of the world ; it is, in fact, the only complete 

 memoir on a tropical orthopterous fauna that has been 

 published, and we venture to prophesy that this posi- 

 tion will long remain unchallenged. The faunistic 

 memoirs of Grandidier's " Histoire de Madagascar," 

 which alone can compare with the " Biologia Centrali- 

 Americana," appear to have come to a premature end ; 

 whilst naturalists like Dr. Godman and the late Mr. 

 Salvin, with the energy, public spirit, and sufficient 

 pecuniary resources to institute zoological surveys of 

 other tropical lands, are unfortunately seldom found. 



The first volume of the memoir under notice began 

 to appear in 1893, and it was completed in 1899; it 

 treats of the Forficulidae, Blattidse, Mantidae, 

 Gryllidas, and Locustida. The Forficulidee were 

 worked out by de Bormans, and are referred to forty- 

 one species, of which eight are new to science ; the 

 author merely enumerates the species with descriptions 

 of the new forms, but adds nothing to what was 

 previously known on the taxonomy of the group. De 

 Saussure and Zehntner, on the other hand, in their 

 work on the Blattidse and Mantidae, publish valuable 

 kej'S to the genera and species, and, in order to make 

 the keys as complete as possible, have included a 

 number of extra-Central-American forms ; consequently 

 these treatises have been since their publication 

 standard works of reference. The largest cockroach 

 known, Mcgaloblatta rufipcs, occurs in Central 

 America, and is fully described and well illustrated in 

 this memoir. The authors remark on its resemblance 

 in details of structure to the genus Blabera of a totally 

 different subfamily, and they appear to regard the 

 resemblance as mimetic. This interpretation is 

 obviously erroneous ; mimicry implies the superficial 

 resemblance of structurally different animals, but 

 Megaloblatta is superficially very different from 

 Blabera, especially in colouring, and the structural 

 resemblances of the two forms must be due either to 

 convergence in development or to genetic relationship ; 

 for our own part we are inclined to favour the latter 

 KO. 2061, VOL. 80] 



view, and to believe that the systematic position of 

 Megaloblatta has been wrongly determined. 



Since Brunner von Wattenwyl once exclaimed 

 enthusiastically that the system of classification 

 of the Gryllidae evolved by de Saussure was 

 not the system of M. de Saussure, " mais 

 bien celui du Cr^ateur Lui-meme," it is only 

 fitting that to the Swiss naturalist should have 

 been entrusted the study of the Central American 

 species, and entomologists may be congratulated on 

 now possessing a most illuminating monograph of a 

 difficult but fascinating group of insects. De Saussure 

 was a systematist who delighted in discovering the 

 relation of structure to function, and his entomological 

 writings are full of references to the bionomics of the 

 insects he studied, and of ingenious suggestions as to 

 the use of the structures that they present. When dis- 

 cussing, in the memoir now reviewed, the presence of 

 four cerci in the genus Tridactylus, a character unique 

 amongst the Orthoptera, he alludes to the amphibious 

 habits of these little crickets, and suggests that the 

 appendages serve to hold an air-bubble when the in- 

 sects dive and swim under the surface of the water. The 

 various modifications of elytral structure and venation 

 to form stridulating organs in the Gryllidae and 

 Locustidae are admirably explained and clearly figured ; 

 the fact is mentioned that many of the apterous 

 Stenopelmatinee are endowed with auditory organs on 

 the front tibiae, and that stridulation is produced, as in 

 the Acridiidae, by the friction of the hind femora, which 

 are roughened on their inner aspect, against an apposed 

 surface — in this case the sides of the abdomen. 



The second volume, containing a monograph on 

 the Acridiidae by L. Bruner and A. Morse, and a list 

 of Phasmidae compiled by R. Shelford from the 

 recent monograph on the family by Brunner von 

 Wattenwyl and Redtenbacher, bears the dates 1900- 

 1909. The considerable period of time elapsing 

 between the commencement and the completion of this 

 volume is partly to be accounted for by the difficulty 

 of working out the large collections of the difficult 

 family of Acridiidje, and partly by the conditions 

 imposed by the Austrian entomologists when they 

 undertook the determination of the Godman-Salvin 

 collection of Phasmidae. They were unwilling to anti- 

 cipate by preliminary memoirs their exhaustive mono- 

 graph of the Phasmidae of the world, and would only 

 undertake to describe the new genera and species from 

 Central America in the monograph itself; consequently 

 it was impossible to publish anything on these insects 

 in the " Biologia Centrali-Americana " until the 

 monograph appeared in 1906-1908. The plates illus- 

 trating the Central American species were prepared 

 some years ago, but since, in some cases, the views on 

 nomenclature of Brunner von Wattenwyl and Redten- 

 bacher were subsequently modified, the legends on the 

 plates do not always correspond with the names of the 

 species as published in their monograph; such dis- 

 crepancies as exist have, however, been explained in 

 the references to the plates. The memoir on the 

 Acridiidae is a valuable piece of work, and adds largely 

 to our knowledge of them ; some of the keys to the 

 genera in the different subfamilies are, however, of 

 most portentous length, occupying ten or twelve quarto 



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