BRITISH GENERA, IN THE ORDER THYSANOPTERA. 4o9 



Art, XLI. — An Epitome of the British Genera, in the Order 

 Thysanoptera^ with Indications ofafeio of the Species. By 

 A. H. Haliday, M. a. 



Ordo. — Thysanoptera. 



Metamorphosis semicomjjleta — AIcb quatuor subceqiiales, hand 

 •plicatce- nee reticulata; longe ciliatce ; anticcefirmiores. — 

 Os, hatistellum breve, dejlextan, carnosum, siphona hise- 

 iiun includens, palpisque 4 instructiim. — Tarsi apice vesi- 

 culosi, exungues. 



Gen. Thrips. . Linnceus. De Geer. Gcoffr. Fabr. &c. 



Physapus . De Geer. Act. Hohn. 

 Ordo Thripsites Newman. 



Body elongate depressed, with the segments all inosculating by a 

 broad surface. Head flat above, the face inclined backwards, the 

 mouth descending under the propectus. The parts of the mouth 

 are united to form a short conic sucker, more fleshy than horny, 

 and not retractile. The labium, which composes the posterior half, 

 has the three usual segments distinct, the stipes (mentum) being the 

 longest, the ligulce shortest ; the palpi are inserted in a narrow 

 membranous space between these last. The maxillce are flat, tri- 

 angular, without division or articulation, their base coalescing with 

 the scape of the labium, so that they have no free motion. A little 

 beyond the middle and near the anterior edge are seated the 

 palpi, which are longer than the labial pair. The maxillae are 

 applied to the edges of the labium, so that they almost meet at 

 the point and enclose in front a triangular space occupied by the 

 clypeus and labrum. The clypeus is transverse, but not symme- 

 trical ; being longer on the leftside, its anterior line descending 

 obliquely in that direction. The labrum seems to be wedge-shaped 

 or triangular ; (but I have scarcely yet separated it satisfactorily.) 

 The mandibles are setaceous, with a bulbous base appearing close 

 to the edge of the maxillee, under which they dip immediately, 

 becoming internal, and by their junction towards the tip forming 

 a two-valved syphon. The compound eyes are lateral and separate. 

 The antennae longer than the head, of eight or nine joints, but 

 sometimes seeming to have only five or six ; filiform or capilla- 



