200 [September, 



whether he could find any structural characters by which to separate 

 the forms. This he kindly consented to do, and passed all my speci- 

 mens (supplemented by those in his own collection, making a series 

 of between 90 and 100 specimens) in review under a strong power of 

 the microscope ; his report was that he could detect no structural 

 character by which to separate them, and that he thought it highly 

 probable that my conclusion as to the specific identity of all these 

 specimens was correct. 



[Mr. J. E. Collin, of Newmarket, who has recently examined the species of 

 Norellia in Mr. Verrall's Collections, sends me the following notes : — 



" I believe every true species of Korellia has the genital plates of the male 

 (those processes at the end of the fifth ventral segment which are always plainlj 

 visible) of a different shape to those of its allies, at least the following species all 

 differ in that respect : — spinimana, striolata, liturata, spinigera, and alpestris, and 

 I consider that a close examination of that character will decide the limits of 

 variation in the species spinimana. The exponents of the genus in Mr. Verrall's 

 British Collection consist of three species, apinimana (several of which were Col. 

 Yerbury's captures), liturata, and a single male spinigera. 



" N. apinimana differs from the other two in being larger and in having five 

 pairs of dorso-central bristles on the thorax, while I believe there are always more 

 (generally three) strong bristles or spines underneath at the tip of the posterior 

 femora. 



"iV. liturata has the disc of the abdomen black haired, while the whole of the 

 abdomen is pale haired in N. spinigera. 



" With regard to Continental specimens, N. striolata though like spinimana 

 in having five pairs of dorso-central bristles, is however much larger and darker, 

 with longer, more slender, and more pubescent legs, and fewer (generally only one) 

 stout bristles or spines underneath at the tip of the posterior femora. iV. alpestris, 

 a quite distinct species, is hardly likely to occur in Britain." — J. W. Y.] 



The late Dr. Meade (Ent. Mo. Mag., August, 1899, p. 173) quotes 

 seven species of the genus as British or reputed British, viz., 

 spinimana, Jlavicauda, nervosa, striolata, armipes, spinipes and liturata. 

 Of these I consider the British specimens of the first four to be forms 

 of one species ; according to Becker's remarks {I.e. p. 127) the fifth 

 species, armipes, appears to be a doubtful one ; the next, spinipes, has 

 been transferred by Eondani and Becker to the genus Achantholena, 

 and as it has not been met with within our limits during recent years 

 it had better be relegated to the reputed list : this will only leave 

 two British species, viz., spinimana and liturata, and to these a third 

 species, spinigera (requiring further confirmation) has to be added. 



Following the table given by Becker ij.c.) the following seems a 

 key to our British species of the genus : — 



