636 DESCRIPTIONS OF PLATES. 



able tooth, c. 5, Internal maxillary palpus, a, Basal joint, b, Apical joint. 

 A, External maxillary palpi. Fig. 11, Labium of Libellula. , The true 

 labium. I b, The lateral lobes, which appear to be modified labial palpi, 2 2, 

 These would then be the second joints of the labial palpus. Fig. 12, Maxilla 

 of Sphex (Ammophila) arenaria. I, Cardo. 2, Stipes. 3, Squama. 4, 

 Mando, here forming the membranous sheath of the tongue and labium. 



a, Filiform palpus. Fig. 1 3, Maxilla of Barynotus obscurus. a, Conical 

 palpus, b, The maxilla, with four teeth on its inner edge (Germar). Fig. 14, 

 Maxillary palpus of Mehmdrya. Fig. 15, Labial palpus of Oxyporus. a, The 

 groove which exhibits after the death of the insect the palpal surface. Fig. 16, 

 Maxillary palpus of Lymexylon navale. Fig. 17, Maxillary palpus of Alracto- 

 cerus necifdaloides (Kirby and Spence). Fig. 18, Maxillary palpus of Bem- 

 bidion (Sturm). Fig. 19, Ditto of Trechus (it.)- Fig. 20, Ditto of T-rox 

 sabulosus. Fig. 21, Maxilla of Hydrophilus piceus. 1, Cardo. 2, Stipes. 

 3, Squama. 4, Mando. 5, External lobes, consisting of a, the basal joint, 

 and b, the hooked, hairy, apical joint. A, Palpus, Fig. 22, Maxillary palpus 

 of Gnjllnlalpa milyaris. a, The swollen palpal surface. Fig. 23, Terminal 

 joint of the same palpus with the dried up surface, a. Fig. 24, Labial palpus 

 of Noctua libatrix (Savigny). Fig. 25, Ditto of Lithosia pulchella (ib}- 

 Fig. 26, Maxilla of Banchusfalcator. The figures the same as in fig. 21. 



PI. V. Fig. 1, Proboscis of a Musca. A, The fleshy lip. a, The peduncle. 

 , A portion beyond the knee, y, The knob. B, The seta within the chan- 

 nelled excavation of the lip. C C, The one-jointed palpus. Fig. 2, Seta? which 

 lie in the fleshy lip of Tabanus. a,Labrum. b b, Mandibles, cc, Maxilla?, d, 

 Tongue. C C, Two-jointed maxillary palpi. Fig. 3, Proboscis of Tabanus seen- 

 from above ; the letters as before. Fig. 4, The same from beneath, d d, The halves 

 of the knobs of the labium. C C, Palpi of the maxilla?. Fig. 5, Labrum from 

 beneath (Savigny). Fig. 6, Mandible (ib.). Fig. 7, Maxilla (ib.). c, Maxilla. 

 C, Two-jointed palpus. Fig. 8, Head of Cimex rufipes seen from beneath. 

 A A, Eyes. B B, First joints of antenna?, a, Labrum. I b, Four-jointed 

 sheath of the proboscis produced by the growing together of the labial palpi. 

 Fig. 9, Clypeus of the same, with the rostral seta extended. , Labrum. 

 c, Mandible still united, d d, Maxilla? (Savigny). Fig. 10, Head of Cimex 

 rujipes, in which the upper integument is removed. A A, The eyes. 

 c c, The mandibles, with the muscle which affixes each to the occiput. 

 d d, Maxilla? attached by muscles to the tongue, e, Tongue. Fig. 11, Head 

 of Nepa cinerea seen from above. A A, Eyes, a, Labrum. b b, Sheath of 

 the proboscis or labium. Fig. 12, The three-jointed sheath of the proboscis 

 seen from beneath. Fig. 13, Proboscis of Nepa cinerea separated (Savigny). 



b, Proboscideal sheath, c c, Mandibles, d d, Maxilla?, e, Tongue, at the 

 base of which is the entrance to the oesophagus. Fig. 14, Labrum of Nepa 

 ,-unrca seen from beneath (Savigny). y, Clypeus from within, h, Reflexed 



