1921.J 85 



p. vrsfdlix Fouivi'. 



Tliis species is one of tlie least variabU' in tlic LToniis, and specimens 

 in which the A^ellow hairs dividing tlie black and white ones of the 

 abdomen are absent, are rare in the fresh specimens of the J , though 

 these hairs naturally fade to white on long exposure. Some males 

 resemble the females in having the first abdcminal segment entirely 

 black-haired, but more often the haii's are yellow, either wholly or in 

 part. The 3'ellow thoracic band is sometimes more or less darkened by 

 admixture of black hairs. 



P. harlndelUis K. 



A rather constant species, the white tail of the <$ in some examples 

 more sordid than in others, but I have seen none with this part brightly 

 yellow. 



In the female, yellow hairs sometimes cover the whole scutellum ; 

 in other examples a pale fringe is formed only posteriorly, and even these 

 hairs may be sordid, so that possibly the thorax is sometimes without 

 any posterior band. Smith, in fact, records such variation in both sexes, 

 but as he included rjuadricolnr in harhiiteUus, it is likely that he was 

 looking at specimens of the former. The basal abdominal segment is 

 entirely black in two examples from Scotland that are before me, but 

 similar specimens are common in the South of England, where, in other 

 individuals, the lateral tufts and the a]>ical fringe of the same segment 

 are yellow. These yellow hairs may form a distinct band, which is 

 usualh', if not always, more or less interrupted in the middle. 



P. cpiadricolor Lep. 

 More variable than the preceding species. 



1 (4) Third and fourth segments with white or almost wliite liaiis, except 



that ill some speciniens the former has dark clotliin<>- hasally. 



2 (3) Basal abdominal segment entirely black-haired. (In this variety the 



thoracic band is liable to become dusky and even to appear inter- 

 rupted in the middle) var. a. 



3 (2) Basal segment more or less conspicuously yellow-haired 



.... var. /3 (normal form). 



4 (1) Third and fourth segments with conspicuously yellow hairs, (lu a 



speciiueu from Scotland the yellow hairs of the first abdominal 

 segment are more sordid and less extensive, and the posterior yellow 

 band is narrower than in a Devonshire example) 



.... var. y. 

 ?$• 



1 (2) Basal abdominal segment with yellow hairs, sometimes forming a 



distinct apical hand var. a. 



2 (1) Basal segment entirely black-haired var. j-i. 



