10 Rev. T. A. Marshall's Monograph of 



maxillary smaller than the rest, the 3rd stoutest, the following elon- 

 gate, nearly equal. Antennae about 55-jointed. Thorax pubescent; 

 mesonotum and scutellum rather shining, finely and sparingly 

 punctulate. Wings more or less infumated or tinged with rufous ; 

 squamulaeand stigma black; nervures fuscous or fusco-rufescent, lighter 

 towards the base ; 2nd discoidal areolet completely closed. Legs 

 rufous ; hind tarsi and tips of tibite of the same pair blackish. 

 Abdomen depressed for the greater part of its length, slightly com- 

 pressed near the 'apex, sessile ; 1st segment one half longer than 

 broad, hardly contracted at the base, faintly margined, covered with 

 rugosities which become longitudinal posteriorly, and surmounted by 

 a medial carina which is effaced before the hind margin ; this 

 segment is rufous more or less at the apex ; segments 2-3 are also 

 rufous ; 4 rufous with the hind margin black, or black with the base 

 rufous, or even entirely black ; the longitudinal striae extend as far 

 as the middle or two thirds of the 3rd segment, the margin of which, 

 and the whole of the following segments are smooth, and very 

 vaguely punctulate ; the ventral surface is of the same colour as the 

 dorsal, but the red extends over the first segment ; a distinct fold 

 runs throughout the ventral surface ; the terebra issues from the 

 anal extremity, and not from a ventral fissure. $ Similar ; 

 antennae longer, with 65-68 joints ; abdomen not compressed at the 

 apex, and shewing one more segment than that of the $ ; apical seg- 

 ments black. Length, 3^ ; exp. 6| lines. 



Var. $ First abdominal segment entirely rufous. 



Parasite of the diptera Lipara lucens, Meig., Z. tomentosa, 

 Macq., and L. similis, Schiner, all three of which are 

 abundant in the islands and on the banks of the Danube, 

 near Vienna, forming galls on Phragmitcs communis. The 

 size of P. lipane varies naturally as that of its victim, the 

 specimens proceeding from L. lucens being the largest. 

 The cocoon is of a deeper rufous than that of the flies, 

 more strongly compacted and more narrowly cylindric ; 

 the parasite, in order to escape, perforates the culm of the 

 reed near the top. The species of Lipara are rare in 

 Britain, and hence the presence of this parasite was not 

 suspected until, by the kindness of Mr. Bignell, I was 

 shewn the unique specimen in Mr. Dale's cabinet, ticketed 

 as having been bred fi'om L. lucens. P. li2Mr£e is also 

 recorded by Van Vollenhoven as taken in Holland. 



