Feb. 19, 1874] 



NATURE 



299 



as has been done by Dr. Schmidt in the service of astro- 

 nomy on the Hill of the Nymphs, over against the 

 Acropolis. 



G. F. RonwELL 



THE AC RID ID. E OF NORTH AMERICA 

 Synopsis of the Acn'didcT of North America. By 

 Cyrus Thomas, Ph.D. Published in Vol. v. of Report 

 of the United States Geological Survey of the Terri- 

 tories. Pp. 1-262. (Washington, 1873.) 

 IN a prefatory note to this volume the United States 

 Geologist, F. V. Hayden, tells us that Prof. Thomas's 

 work on the Acrididas of North America is published " in 

 the belief that it is a substantial contribution to natural 

 histor)- ;" and certainly it is impossible, on a perusal of 

 the work, not to share in this belief; it is, moreover, 

 another proof of the great boon conferred upon natural 

 science by public surveys and Government expeditions. 

 Serious and extended works on natural history (except, 

 perhaps, those relating to some few very popular branches 

 of it) would seldom be produced, or in many cases their 

 materials be collected, if it were not for the assistance of 

 natural history societies, public surveys, and expeditions ; 

 organisations of these kinds can afford to disregard 

 the commercial aspect of the question, and are able to 

 bestow upon the public, works which private enterprise 

 would seldom venture upon. Among insects, the Or- 

 thoptera (of which order the Acrididse are a well- 

 defined family group) are certainly not the most popular 

 among entomologists, though, for many reasons, of 

 great interest to others. Few persons but have some 

 cherished association with, for instance, the persistent 

 chirp of the cricket on the hearth, or the shrill stridula- 

 tions of some of the grasshoppers ; there are, again, ^w 

 more wonderful sights in the insect world than a flight of 

 locusts ; and few natural scourges are more terrible than 

 those inflicted by the devastations of these rapacious 

 creatures ; the walking-leaf and stick insects (Mantidae and 

 Phasmidre) are also very popular objects for sightseers 

 in natural history museums. The lack of general popu- 

 larity among collectors and students arises probably 

 in great measure from the Orthoptera being com- 

 monly less sightly as cabinet objects than some other 

 orders of the Insecta, though perhaps it arises as 

 much or more from the paucity of works combining both 

 a general and special treatment of the whole, or of well- 

 defined groups, of the order under consideration. Dr. 

 Thomas's work is undoubtedly calculated to encourage 

 the study of the large group included under the Acrididtr, 

 and to be peculiarly acceptable to American entomologists, 

 for it not only describes a large number of North Ameri- 

 can species (both known species as well as new ones), but 

 it gives, in an " Introduction," pp. 9-45, a concise view of 

 the general classification of the Orthoptera, with the rela- 

 tion of the Acrididffi to the other sub-ordinal groups, their 

 structure, internal and external, and the distribution of 

 genera and species over North America. This introduc- 

 tory part of the work is illustrated by two remarkably 

 clear and good woodcuts, showing all the different portions 

 of external structure, with the name of each part. 



The remarks of Prof Thomas, in the chapter on 

 Classification, bring strongly before us the difficulties and 



imperfections involved in a linear arrangement of any 

 portion of the animal kingdom ; but if a real genealogical 

 relationship be that which exists between all living 

 creatures, then it is apparent at once how comparatively 

 unimportant is (generally speaking) the mere linear 

 arrangement of the series ; it is, indeed, the only possible 

 one on paper, but in reality some of the most important 

 relationships do not run in one unbroken line, but in 

 lines diverging at many different angles, and in many 

 different planes. Dr. Thomas considers the Orthoptera as 

 arising from the Crustacea, and, after reviewing the 

 various extant arrangements of their families, divides that 

 under consideration — AcridiD/E {i.e. the saltatorial 

 Orthoptera, or Grasshoppers with comparatively short 

 antennae), into two sub-families — ACRIDIN.E and Tetti- 

 GIN.E ; the former of these is sub-divided into three 

 divisions : — Conocephalides, Orthocerides, and 

 XiPHOCERlDES, forming (in the order in which these are 

 here given) seven groups: — I. Proscopini ; 2.TRYXALINI; 

 3. TrIGONOPTERYGINI ; 4. OIdIPODINI ; 3. ACRIOINI ; 



6. Xiphocerini ; 7. Phvmatini (?). The three first of 

 these groups belong to the Conocephalides, the two next 

 to the Orthocerides, and the two last to the Xiphocerides. 



The subfamily Tettigtn^E is undivided, and consists 

 of a single group, Tettigini. 



A useful and concise Synoptical Table gives the 

 leading characters of the author's sub-families and sub- 

 ordinate groups ; and another Synoptical Table of the 

 United States genera (p. 49), as well as an excellent 

 plate containing seventeen figures, will give great assist- 

 ance to the student of the American species. Pp. 55 — 

 245 are wholly occupied by scientific descriptions of 

 species, genera, and other larger groups. This portion of 

 the work is divided into two parts, the first treating of 

 the Acrididae of the United States (pp. 55 — igo) ; the 

 second (pp. 195 — 245) of those of North America, not 

 found in the United States. The number of genera cha- 

 racterised as North American is 45 ; that of species 227. 

 In the United States (exclusive of Tcttigina:, which con- 

 tain 3 genera and 12 species) are, at present known, 125 

 species of 25 genera ; of the former, forty, and of the 

 latter, four are described as new ; and six others also are 

 described as not hitherto known to be represented in that 

 more restricted locality. At pp. 3 — 5 will be found a boon 

 to the American orthopterologist in the shape of a list of 

 those authorities which contain descriptions of the genera 

 and species of Acrididre belonging to the North Ameri- 

 can fauna. Another exceedingly useful feature of Dr. 

 Thomas's work is a glossary at the end explaining the 

 technical terms (to the number of upwards of 200) used 

 in the scientific descriptions ; the utility of this glossary 

 will, no doubt, be felt far beyond the circle of students 

 and collectors of the Acridids. 



OUR BOOK SHELF 

 Daily Bulletin of Weather Reports, Signal Service, 

 United States Army, taken at 7.35 a.m., 4.35 p.m., and 

 II P.M. U'ashi?igtoM Mean Time, with the Synopses, 

 Probabilities, and Facts for the Month of September 

 1872. (Washington, Government Printing Office, 1873.) 

 This is a quarto volume of upwards of iSo pp., contain- 

 ing besides 90 weather-charts — three for each day of the 

 month of September 1872. The volume is published for 



