1911.] ^03 



HELP-NOTES TOWARDS THE DETEEMINATION OF BRITISH 

 TENTHBEDINIDM, &c. (28). 



BY THE REV. F. D. MOKICE, M.A., F.E.S. 



MACROPHYA, Dahlb. 



The statement in my last paper that the abdomen of Perinenra 

 riihi, Pz., is " fulvous-yellow (testaceous) " is correct as to the male, 

 but requires amendment in the case of the female. In that sex the 

 sides and the whole ventral surface of the abdomen are much infuscated 

 and only the central portion of its dorsum distinctl}^ reddish, some- 

 what as in Thrinax macula, Kl. (Ent. Mo. Mag., 1908, p. 193). I 

 might have mentioned also that in this insect the thorax is prettily 

 marked with white above in both sexes, and that the ^J stigma is nearly 

 unicolorous (yellow) , while in the $ it is particoloured (the base yellow 

 but the apex black). 



Coming now to the genus Macrophya, I wish first to correct another 

 inexactitude which I have only just detected in my " Table of G-eneric 

 Characters" (see Ent. Mo. Mag., 1903, p. 198, line 16). There I say 

 that in Macropliya, Almntus, and Tenthredo the least distance between 

 the eyes is " less " than the width of the clypeus. This should be 

 qualified by adding " or if not so, then with short thick antennae and 

 abnormally elongate hind coxae," to meet the case of Macrophya 'piinc- 

 tuni album, L., which, as Dr. Enslin has pointed out, differs from its 

 congeners in having eyes lying " outside the clypeus," and separated 

 therefore by at least the full width of the latter from each other. 



The structural differences between Macropliya species, though not 

 imimportant, are seldom conspicuous ; and in most cases a determina- 

 tion can be arrived at simply from the colour-characters. Some of 

 these, it is true, are inconstant and tmreliable, but the majority of them 

 are practically invariable — such as the colour of the stigma, and the 

 red yellow or white markings on certain joints of the legs, which are 

 often very characteristic and conspicuous. 



Comparatively a very small proportion (less than one- sixth) of the 

 59 Palaearctic species lately tabulated by Dr. Enslin occur in this 

 country ; but such as do occur seem to be mostly fairly common, at 

 least in the southern counties. An exception is alhipuncta, Fall, (not 

 to be confounded ynth. punctum aZfewm, Linn.), which I have never 

 seen except from Germany, but which is, I doubt not, correctly re- 

 corded by Mr. Cameron as British. I include this species therefore in 

 my Tables, but mark it with a t to show that I cannot personally 

 vouch for its occurrence. Mr. Cameron's hxmatopus, however, I omit, 



I 2 



