A GUIDE TO THE STUDY OF BRITISH WATERBUGS. 37 



as thus described, could not be taken as the type, and I selected 

 spinosa, Fabr., as available. Mr. Kirkaldy asserts that this 

 " is invalid in any case, as Stal places it at the head of his sub- 

 genus Cosmopsaltria." Of the latter genus Stal had (Berl. Ent. 

 Zeitschr. x. p. 170 (1866) ) previously fixed the type as C. doryca, 

 Boisd,, including in it both spinosa, Fabr., and flavida, Guer. 

 These species cannot, however, be regarded as congeneric with 

 Boisduval's doryca, and Mr. Kirkaldy's contention is untenable, 

 while he has placed a forced interpretation on my sentence 

 (" nom. nee descript."). 



With the other opinions of Mr. Kirkaldy I am not concerned ; 

 I merely wish to correct his statements, and to desire accuracy 

 in criticism. 



A GUIDE TO THE STUDY OF BRITISH WATERBUGS 

 (AQUATIC HEMIPTERA). 



By G. W. Kirkaldy. 



(Concluded from vol. xxxix. p. 157.) 



I COMMENCED this " Guide " in August, 1898, in the thirty- 

 first volume of the ' Entomologist,' and certainly never antici- 

 pated that ten years would pass before it was completed. This 

 slowness has been due to causes beyond my control, primarily to 

 my removal to the Hawaiian Islands, and secondly to a severe 

 accident which has sadly delayed all my work ; but I trust that 

 the irregular appearance of these hints on the study of, perhaps, 

 the most fascinating, morphologically and biologically, of all 

 the Hemiptera — that is to say, of all animals — has not dis- 

 couraged any of my readers who may have felt some inclination 

 to study them. 



I proposed to provide a list of all the British species, with 

 their county distribution, but the publication, mostly since I 

 left England, of the 'Victoria Natural History' series, none 

 of the volumes of which I have seen, has compelled me to omit 

 this part of my plan. 



Later on I hope to revert to this subject, but I think that it 

 is better to close the "Guide" at this point, hoping that the 

 Editor will allow me to make further observations at some 

 future time. 



The following corrections should be made : — 



Vol. xxxii. p. 296, line 1 of the table, read " First segment of 

 middle tarsi not more than 2^ times as long as the second," . . . 

 and the corresponding entry, " First segment of middle tibiae 

 rarely (if ever) less than three times as long as the second 

 segment." 



Vol. xxxiii. p. 150, for "figs. 31-4" read "31, 32, 34"; for 

 "figs. 35-9" read "35-6"; delete " 40-." 



