65 PLATE XVII. ILLUSTRATIONS OF TWO ROSTRATED LOCUSTID^. The insects represented in the opposite plate exhibit a singular departure from the ordinary form of the Locusts, in the front of the head being produced into a long rostrum somewhat like that of the typical Fulgorse. Amongst the grasshoppers with long antennae there is a genus, Copiophora, in which the head is elevated into an erect and pointed horn, and in Mesops and Proscopia, two genera of Locusts, we find an approximation to these two insects. Notwithstanding the great elongation of the head in front of the eyes, I refer the unique insect represented in the upper figure to the genus Opsomala of Serville rather than to his genus Mesops, because the antennse are inserted near the eyes, whereas in the latter genus (which has much more the habit of Truxalis) the eyes are " places assez loin des antennes," and because the same organs are not ensiform, thus assigning the insect to Serville's second divi-sion of Opsomala with the "antennes composees d'articles peu aplatis et point elargis." OPSOMALA GLADIATOR, Westw. (PI. 17, fig. 1). Luteo-fusca, virescente parum tincta, capita antice in rostrum (prothorace duplo loiigius) pro-ducto, antennis rostro brevioribus gracilibus, alis hyaliuis vix incoloratis, abdomine longissimo, pedibus 4 anticis brevissimis. Long. Corp. (rostro incl.) unc. 3i ; long capitis unc. 1, ante oculos unc. J. Expans. tegni. unc. 3f . Habitat Sierram Leonam. In Mus. D. Hope. This is a giant in the genus Opsomala, being nearly twice as long as the largest described species. It is entirely of a luteous brown colour, slightly varied with darker browu, with a paler oblong patch on each side of the upper surface of the prothorax. The head is produced into a rostrum nearly three-fourths of an inch long, its upper surface being nearly continuous with the disk of the head, and gradually narrowed from the eyes to the tip ; the upper surface flat along the middle, but with the sides towards the eyes deflexed ; the under surface of the rostrum forms a very sharp edge, and is slightly curved, the tip being obliquely truncate. The eyes are oval and slightly elevated ; the antennaj are placed at the base of the lateral channel which extends from the base to the apex at the sides of the rostrum ; they are slender, filiform, and not so long as the rostrum. The prothorax is sliglitly rugose, with the dorsal carina scarcely elevated, and with three transverse very slight impressed lines across the middle of the back. The tegmina are narrow, not so long as the abdooieu, with the apex almost rounded; they are of a pale luteous-brown colour, with the veins varied with darker brown ; the wings are almost colourless ; the middle of many of the cells is, however, rather clouded with a tinge of pale brown. The abdomen is very compressed and sliiuing, with the anal ap-pendages wliitish. The four fore legs are very short, and the hind pair are scarcely longer than the abdomen ; the femora terminating on the outside in an elongated spine. The pro-sternum is armed with a short spine, and the mcso-and metasternums are broad. NO. V. — 1st JANUARY, 1842. P
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