128 APID^!. 



Thorax — the collar, tubercles, a lunate spot beneath them, the 

 tegulae, and scutellum yellow ; the legs pale ferruginous, the ante- 

 rior and posterior coxae yellow in front, the intermediate pair have 

 usually a minute spot at the sides and another on the pectus in 

 front of each ; the posterior femora black at their base, the anterior 

 and posterior pairs usually rufo-testaceous, but sometimes black, 

 the tibiae and tarsi varied with yellow ; the wings subhyaline, their 

 apical margins faintly clouded. Abdomen : the second and third 

 segments have on each side a large transverse macula, pointed 

 within ; the fourth and fifth a transverse fascia, attenuated in the 

 middle, the sixth an entire broad yellow one. B.M, 



Var. j3. The band on the fourth segment interrupted. 



Yar. y. The basal segment having two minute yellow dots. 



Yar. S. Margins of the segments of the abdomen rufo-piceous. 



This is the most variable species of the genus, both in size and 

 coloration ; it is the parasite of Halictus hucozonius, and probably 

 also of H. cylindricus. It is found in considerable numbers on wild 

 thyme and on the ragwort (Senecio jacoboea) in July and August, and 

 sometimes also as late as September. The male seldom varies in its 

 colouring, a red variety being a great rarity, whilst the female runs 

 into endless variations of colour and size. 



19. Nomada jacobaBse. 



iV. atra, pedibus ferrugineis, scutelli punctis duobus abdominisque 

 maculis fasciisque flavis. 



Nomada jacobaeas, Panz. Faun. Germ. 72. 20 <$ . 



Schtiff. Germ. Zeits. i. 286 <$ $ . 



St.-Farg. Hym. ii. 479. 



Smith, Zool. ii. 594 ; Bees Great Brit. 137. 



Nyland. Notis. ur Stilish, pro Faun, et Flo. Fenn. i. 175. 



Schenck, Nass. Bien. 181. 



Thorns. Opusc. Ent. 92 ; Hym. Scand. ii. 173. 

 Apis jacobaeae, Kirhy, Mon. Apum Angl. ii. 201. 

 Apis flavopicta, Kirby, lib. cit. 202. 



Female. Length 4-4^ lines. — Black ; the anterior margin of the 

 clypeus, the labrum, and mandibles yellow ; the tips of the mandi- 

 bles and the margin of the clypeus narrowly ferruginous; the 

 labrum has a minute tooth in the middle ; the scape and the base 

 of the flagellum ferruginous beneath. Thorax : the collar, tuber- 

 cles, a spot on the breast, the tegulae, and two spots on the scutel- 

 lum are yellow ; the wings subhyaline, their margins clouded ; the 

 legs ferruginous, varied with yellow ; the coxae and trochanters 

 black, their tips ferruginous ; the intermediate and posterior coxae 

 yellow in front. Abdomen : the first segment has a subinterrupted 

 fascia, the second a large macula on each side, acute within, the 

 third a narrow line on each side, and the following segment a 

 broad fascia, yellow ; the apical segment yellow. B.M. 



