Plech'scus] 



BRITISH ICHNEUMONS. 



to twenU'-six jointed, with scape somewhat short; flai;eUar joints elongate, 

 cylindrical and slender, with the first longer than second. Thorax with 

 the mesonotum glabrous and nitidulous, and only apically finely pubes- 

 cent; notauli wanting or at most only apically distinct; metathoracic 

 areae distinct, though costulae always wanting; spiracular area hardly 

 extending beyond centre. Abdomen with basal segment rugosely punc- 

 tate, its spiracles almost before centre ; terebra distinctly exserted and 

 usually elongate, with valvulae slender and elongately pilose. Legs 

 slender, with onychii and pulvilli small. Areolet oblique, usually entire 

 but if externally obsolete the inner nervure is elongate and distinct; basal 

 radial abscissa strongly curved; parallel nervure emitted from centre of 

 brachial cell ; nervellus usually distinctly geniculate and sometimes inter- 

 cepted. 



(12). 



Table of Species. 



Petiolar area not extending beyond 

 metathoracic centre, nor terebra 

 longer than abdomen. 



Larger ; legs and antennae stout ; 

 hind tibiae hardly constricted. 



Anus compressed ; propleurae pale ; 

 terebra longer than half abdomen 



Anus hardly compressed; thorax- 

 dark ; terebra shorter than half 

 abdomen 



Smaller; legs and antennae slender; 

 hind tibiae distinctly constricted. 



Basal segment elongate, linear; bod}^ 

 not coarctate. 



Flagellum with nineteen joints ; peti- 

 olar spiracles strong 



Flagellum with eighteen joints ; peti- 

 olar spiracles normal 



Basal segment shorter and broader ; 

 body coarctate. 



Hind tibiae infuscate; terebra longer 

 than hall' abdomen 



Hind tibiae pale ; terebra shorter than 

 half abdomen 



Petiolar area extending beyond cen- 

 tre ; terebra lonyer than abdomen 



I. coi.LARis, Grav. 



2. EURISTIGMA, ThofllS. 



3. TENER, Forsf. 



4. CANALICULATUS, Fursf. 



5. TEREllRATOR, Forst. 



6. MELAXOCERUS, F'ursf. 



7. CO MAI UN IS, Forst. 



1. collaris, Grav. 



Plcctiscus collaris, Gr. I.E. ii. 987 ; Hal. Ann. Nat. Hist. 1839, p. 116; Forst. 

 Verb. pr. Rheinl. 1871. p. S9, ? ; Thorns. O.K. xii. 1300, cT ? ; Strobl, Mitt. Nai. 

 Ver. Steierm. 1903, p. 127. 



Head hardly constricted posteriorly, with vertex somewhat broad, 

 cheeks short with no sulci. Antennae stout, filiform and piceous with 

 their base flavidous; of 9 with the penultimate joint transverse, of J 

 slender and elongate with elevated lines on the fifth to seventh joints of 

 flagellum. Thoracic notauli short but deeply impressed; mctathorax 

 shining and obsoletely shagreened, with areola smoother and basall\ 



