ANTHRAX HYPOMELAS. 75 



colour of the base invades a little the basal cells; the 

 dark crossband extends inwards halfw^ay into these cells, 

 runs outwards along the anterior margin down to the end 

 of the marginal cell, reaches the forkcell and leaves the 

 end of the three first posterior cells untouched ; the middle 

 of the fourth posterior cell and especially that of the dis- 

 coidal cell is paler ; the remaining hyaline part of the wings 

 has a rather obscure gray tinge and the hind corner is 

 even brownish. 



A 9 from Arizona in North-America (Neumögen). 



I cannot bring this specimen to one of the many North- 

 American species already described; it cannot even be ar- 

 ranged in one of the groups, into which 0. Sacken has 

 divided them (West. Dipt. 238). 



3. Anthrax hypomelas, Macq. 



Macq. Dipt. ex. II. 1. 76. 63. 



A female specimen from Arizona in North- America (Neu- 

 mögen) belongs, in my opinion, to this species. Though 

 it is not in a very perfect state, it quite evidently shows 

 the black hairs on the sides of the second and third ab- 

 dominal segments, which prevents me to regard it as A. 

 molitor Low (Dipt. Amer. Sept. Cent. VIII. 42), the des- 

 cription of which in other points agrees tolerably well , but 

 in that species the black hairs are found on the fifth and 

 sixth segments. The hind tibiae are beset on the outside 

 with many recumbent bristles, a character common to A. 

 molitor and a few allied species. The radial vein has at 

 its angulous base a small recurrent vein , such as is also 

 to be found in certain individuals of our indigenous A. 

 hottentotta L., with which the nervation of the wings ge- 

 nerally agrees. 



In the Leyden Museum there is also a male specimen from 

 the same locality and very similar to the foregoing female ; 

 however it is considerably smaller (it measures no more 

 than 7 mm., whilst A. hj/pomelas has a length of 12 mm.); 



Notes from the X^eyden IMiiseixrn, Vol. 1~V. 



