236 Mr. E. Saunders' Synopsis of 



6. Bomhus hortorum, Linn. (PI. XII., fig. 6). 



Linn., Faun. Suec, ed. alt., p. 424; Smith, Cat. 

 Brit. Hym., 2nd ed., p. 214. 



Var. = subterraneus, Auct. (nee Thorns.). 

 Var. = Harrisellus. Kirb. 



Head black ; cheeks very long, two-tliirds as long as the eyes. 

 Thorax black, widely yellow anteriorly and posteriorly ; abdomen 

 with the basal segment yellow, the 2nd and 3rd black, the 

 remainder white, or the whole insect entirely black (Harrisellus) ; 

 colom* varying to almost any extent between the two extremes ; 

 tongne very long, almost as long as the body in the 5 and 5; 

 sagittae in the 3' denticulate exteriorly. 



(^ . Head clothed with black hairs ; face very long and parallel- 

 sided ; cheeks shining, very long, more than twice the length of 

 their apex. Antennae with the 2nd and 4th joints of the flagellum 

 subequal, the 3rd very short ; tongue reaching to the posterior 

 coxae. Thorax clothed with black hairs, with a wide yellow band 

 in front, and another across the metathorax ; wings inore or less 

 brownish. Abdomen with the basal segment yellow-haired ; the 

 2nd and 3rd black; the 4th, 5th, and Gth white, and the apical seg- 

 ment black ; beneath clothed with white hairs, Gth segment with 

 black ; 7th with a few bristly black hairs ; 8th somewhat rounded at 

 the apex, with a very small central emargination ; genital armature 

 with the sagittse finely and shai'ply serrate beneath ; squama wide 

 in front, narrowed behind, and i)roduced along the stipes towards 

 its base, tlien turned back and armed with a recurved spine at its 

 apex (see PI. XII., fig. 6). Legs clothed with black or reddish 

 black hairs ; posterior tibiae shining. 



Var. Harrisellus. — Entire insect clothed with black hairs. 



5 and 5 . Like tlie ^ in colour, but more subject to variation ; 

 in the ^ intermediate varieties between the typical form and the 

 black one are rare, in the ^ and 5 they are common ; head shaped 

 as in the 3" ! tongue very long, often as long as the body ; cheeks 

 two-thirds as long as the eye ; posterior tibiae with black hairs. 

 Length. and 5 16 — 22 mm., ^ 12 — 15 mm. 



Hah. Very common, and generally distributed. 



This species has usually been considered as consti- 

 tuting two, but there is no satisfactory structural cha- 

 racter to separate them apart, and the male armature in 

 all the varieties is identical : to subterraneus have been 

 referred the large females of a less bright coloration, with 

 the abdomen rather broader at the apex, and with its 



