248 ANNALS OF SCOTTISH NATURAL HISTORY 



achievement, and with this in mind one can hardly overstate the 

 debt under which Mr. Wingate has laid the increasingly large 

 number of students of Diptera not merely in Durham but in Britain. 

 Simply as a local list, embracing almost one-fourth of our hitherto 

 recorded species, the work would have made valuable contributions 

 to a knowledge of the distribution of the order in this island. But 

 Mr. Wingate has a second object in view. Recognising that, in the 

 present incomplete state of the literature in English on his subject, 

 a bare list is useless to any save an expert, he has brought together 

 a set of keys to the families, genera, and species, by means of which 

 the systematic position of a specimen may be indicated. In the 

 compiling, of these tables all the best continental and home work of 

 the past fifty years has been laid under contribution, with the result 

 that for the first time we have a convenient compendium of the 

 generic and specific characters of the Diptera of Britain. 



In all some 626 sp. are listed, while of the 2880 sp. in 

 VerralPs List, 1901, a guide is given to 2210. In the case of certain 

 genera an important addition is made in the diagnostic features of 

 European species not yet British. In this way some 318 species are 

 referred to. A number of interesting critical notes occur throughout 

 the text. A special word of praise is due to the method employed 

 in describing the wings. By numbering each vein a great simplifica- 

 tion in terminology has been effected. The cross veins are deter- 

 mined by the hindmost of the veins connected, e.g. the anal cross 

 vein becomes X 6. All confusion is avoided by a careful statement 

 of the homologues in continental writers. The description of cells 

 is equally simple and efficient. The usefulness of this part is 

 increased by a fly chart and several plates planned to show concisely 

 the points of difference relied on in the text. Mention must also 

 be made of two excellent pages on collecting and preserving. 



Mr. Wingate is to be congratulated on the completion of his List. 

 The outcome of his own disappointments, it will save many another 

 from a similar experience. Used with discrimination it will be of 

 inim-mse help to beginners, wl : to the advanced student, though 

 the critical determination of spe ies is beyond its province, it will 

 prove a very handy book of reference. J. W. 



