28 BRITISH ICHNEUMONS \Porizon 



Table of Genera. 



(2). I. Calcaria curved and of normal leng-th; 



hind tarsi elongate with joints 



gradually diminishing in length ; 



thorax usually cylindrical . . PoRIZON, Grav. 



(i). 2. Calcaria straight and short ; hind 



tarsi of normal length with second 



to fourth joints gradually shorter, 



but first and tifth abruptly elon- 

 gate ; thorax short and coarctate. 

 (4). 3. Flagellum multi - articulate ; lower 



angle of brachial cell entire ; 



notauli short but distinct ; thy- 



ridii large and elongate - trian- 

 gular . . . . . . DiAPARSUs, Thotns. 



(3). 4. Flagellum often pauci - articulate ; 



lower angle of brachial cell 



sometimes incomplete ; notauli 



wanting or obsolete ; thyridii 



small . . . . Thersilochus, Hohngr. 



PORIZON, Fallen. 

 Fall. Specimen. Hym. (1813), 17; Holmgr. Sv. Ak. Handl. 1858, p. 132. 



Body large or of normal size, rarely small ; abdomen never entirely 

 black. Head rarely subcubical, with frons often smooth. Antennae 

 sometimes attenuate towards their apices, with flagellum multi-articulate. 

 Thorax generally much longer than high ; sternauli always discreted and 

 sternum very often much longer than broad between the anterior coxae ; 

 petiolar metathoracic area very rarely extending beyond centre, basal 

 area not often complete. Abdomen with petiole usually stout, sometimes 

 discally broadly excavate ; second segment very often not transverse, 

 with large and triangular thyridii ; terebra usually stout and strongly 

 reflexed. Legs- with anterior coxae not infrequently small; tibiae some- 

 times short, always with curved calcaria; hind tarsi elongate with all the 

 joints gradually decreasing in length, and base pale-marked. Wings 

 with the stigma not very broad, generally emitting the radial nervure 

 beyond its centre ; brachial cell with its lower angle not open. 



Porizon Italiciis, Grav. (I.E. iii. 780, $ ), was sent from Genoa by Spinola 

 and has, almost certainly erroneously, been considered British ; Marshall 

 places it in Thersilochus, but no one now knows what it is. The same 

 author's P. rufinus {I.e. 754, $ ) is a synonym of Orthopelma Ititeolaior [ef. 

 Ichn. Brit. ii. 1 1 1). To what genus to refer P. lingua?-ms, Hal. (Ann. Nat. 

 Hist. 1839, p. 117, $ ) I am at a loss, though its author, who says "The 

 maxillae and labium inflected in repose extend as far as the coxae of the 

 intermediate legs," did not intend its inclusion in Acrodacljla, as placed 

 by Dalla Torre {ef. Morley, Entom. 19 13, p. 262). 



The7silochiis, Holmgr., comprising the two other genera of this Tribe, 

 was at first distinguished from the present genus by having the antennae 



