.BEES OF GREAT BRITAIN. 137 



ceous beneath. Thorax: the collar, tubercles, a lunate spot 

 beneath them, the tegulsc, and scutellum yellow ; the legs pale 

 ferruginous, the anterior 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 tibise and tarsi varied 

 with yellow; the wings subhy aline, 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, 13. The band on the fourth segment interrupted. , 



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



This is one of the most abundant species of the genus ; it is 

 somewhat local, usually appears towards the middle of July, 

 and is found in great numbers on the Ragwort, but has been 

 met with in greater abundance on the Wild Thyme. The female 

 is subject to very great variation in colouring : the male seldom 

 offers any striking differences ; many hundreds have been exa- 

 mined, but not a single example with the rufous colouring on 

 the abdomen has been discovered. A series of gradual changes 

 from black to red may be met with in specimens of the female. 

 This species is parasitic on Halictus abdommalis. 



20. Nomada Jacobseae. 



N. atra; pedibus ferrugineis, scutelli punctis duobus, abdominis- 

 que maculis fasciisque flavis. 



Nomada Jacobsese, Panz, Faun. Germ, 72. 17 <? . 



Latr. Hist. Nat. xiv. 50. 2. 



Schdff. Germ. Zeits. i. 286. 21. 



St. Farg. Hist. Nat. Ins. ii. 479. 15. 



Smith. ZooL ii. 594. 7 c? $ . 



Nyland. Ap. Boreal, p. 175. 2. 

 Nomada interrupta, Panz. Faun. Germ. 96. 22 (var. $)} 

 Apis Jacoba^se, Kiriy^ Mon. Ap. Angl. ii. 201. 20 $ . 

 Apis flavo-picta, Kirby, Mon. Ap. Angl ii. 202. 21 ? . 



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

 the clypeus more or less yellow; the labrum and mandibles 

 yellow ; the tips of the mandibles and the margin of the clypeus 

 narrowly ferruginous ; the labrum has a minute tooth in the 



