Revie%ics and Book A^ofices. 



277 



actions of the Natural History Society of Northumberland, 

 Durham, and Newcastle-upon-Tyne, and worthily sustains the 

 reputation of these publications. 



The title of this book is somewhat misleading, in two ways. 

 In the first place, it is hardly a ' preliminary ' list, inasmuch as 

 it is the third list of the two-wing-ed flies of the county, which 

 the author has himself published. No doubt it is by inadvertence 

 that no reference of any kind is made in the volume now before 

 us to the two previous lists. The first of these was a full and 

 elaborate one, with localities of the Durham Diptera, which was 

 published in this journal three years ag-o (See the ' Naturalist '^ 

 July 1903, pp. 269-288), and the second was published last year 

 in the ' Victoria History of the County of Durham.' 



In the second place, the title errs on the side of modesty, for 

 this is not so much a list of Diptera of a county, as a series of 

 analytical tables by which to diag-nose almost the whole Dipterous 

 fauna of the British Isles, the exceptions being duly noted in the 

 introductory remarks, and reasons assigned. 



English dipterists (or dipterologists) have so little literature 

 in their own tongue available for the determination of their 

 captures, that they cannot but feel grateful in the highest degree 

 to Mr. Wingate for furnishing them with a work so well calcu- 

 lated in its plan to help the young dipterologist to make out his 

 captures. The dichotomic or tabular method adopted here is 

 a very useful one, as drawing attention to the diagnostic points, 

 and likely to assist the beginner in making out, at any rate, the 

 well-marked and more distinctly characterised species. The 

 actual value of any such tables is not to be gauged by a 

 reviewer, and can only be judged after prolonged use in the 

 actual determination of the species. 



There are seven plates, giving diagrammatic representations 

 of details of external anatomy in various genera. We are 

 allowed to reproduce plate i, what the author calls a 'Fly- 

 Chart,' figuring an imaginary or generalised type of fl}', on 

 which the various morphological features are fully indicated, 

 and fully explained In the introductory chapters. This chart 

 ought to be very useful, and its use ought to tend to accuracy 

 and precision in dipterological investigation. 



The tables give the diagnoses of 2526 species, some being 

 forms not yet known as British, but quite likely to occur, and 

 localites, or statements of distribution in Durham, are cited for 

 the 626 species which the author has found in the district. The 

 work is full}- indexed, and one of the indexes is of the Durham 



1906 August I. 



