253. 

 SIREX JUVENCUS. 



Order Hymenoptera. Fam. Siricidse Nob. — Uroceridae 

 Lat., Leach. 

 Type of the Genus Sirex juvencus Linn. 

 SiREX Linn., Fab., Jur., Panz., King. — Urocerus Geoff"., Lat., Leach. 

 Antennce inserted in front of the face, longer than the thorax, 

 nearly filiform, containing from 1 7 to 23 joints, those of the 

 female composed of the greater number, basal joint the most 

 robust, 2nd globose, 3rd as long as the 1st, the remainder de- 

 creasing in length to the last which is often a little longer (fig. 1, 

 basal joints of antenna of the male from which sex all the dissec- 

 tions were taken). 



Labrum but partially exserted, tongue-shaped, very rigid towards 

 the apex and pilose on the sides (2), 



Mandibles rather small, short, subtrigonate and tridentate at the 

 apex, producing rather soft and long hair externally and inter- 

 nally (3). 



Maxilla uniting at the base of the mentum, not so long as the 

 lip (4*), terminated by a narrow pilose, membranous lobe, twice 

 as long as the Palpi, which are very small and arise from a 

 thickened shoulder of the maxillae j biarticulate? the terminal 

 joint very minute (4). 



Mentum small transverse, narrowed at the base (5). Lip rather 

 large, coriaceous at the base, the apex forming a membranous 

 lobe, thickly clothed with long pubescence. Palpi inserted near 

 the base, very much larger than the maxillary ; triarticulate, 

 basal joint small, 2nd rather longer, 3rd large and clavate, pro- 

 ducing very long hairs, especially on the internal side (5b). 

 Head not large but suborbicular. Ocelli 3, between the Eyes which 

 are small and not quite lateral. Thorax shield-shaped, anterior 

 angles produced. Abdomen lo7ig cylindric, perfectly sessile, acumi- 

 nated, especially in the female. Ovipositor exserted. Wings with 

 2 marginal and 4 suhmarginal cells. Legs rather long, hinder tibiae 

 and tarsi dilated in the males. Thighs short and robust. Tibiae with 

 2 short spurs at the apex, except in the anterior pair, which have a 

 single spine dilated into a lobe near the apex which is acuminated. 

 Tarsi very long, basal joint the longest, 4th minute. Claws strong, 

 bent and bidentate. Pulvilli distinct in the males (8, afore leg). 

 Larvae with 6 pectoral feet, body armed at the apex with a spine. Klug. 



Juvencus Linn. F. S. \575.fem. — noctilioFafe. E. S. 2. 130.22. male. 

 Male dark green, punctured, head thorax and base of abdomen 

 very pubescent, 3rd and 8th joints of the latter purplish, the in- 

 termediate space orange coloured. Eyes legs and wings ochreous, 

 nervures ferruginous. Thighs and hinder legs bluish black, the 

 penultimate joint of tarsus and base of tibia ochreous. 

 Female blackish purple, base and apex of abdomen chalybeous. 

 Legs ochreous, tarsi piceous at their tips. 



In the Author's and other Cabinets. 



