230 STAPH YLINID^. [Qziediiis 



aj. Hind botly at apex, and apex of 



segments, reddish ; legs more or 



less pitehy red ; antennae with 



joints 6-10 less transverse; size 



moderate Q. fulgidus, F. 



{quadripunctalus, Thorns.), 

 bj. Hind body concolorous black ; 



legs black with tarsi entirely red ; 



antennae with joints 6-10 more 



transvci-se ; size smaller . . . . Q. PUNCTICOLLIS, Thorns. 

 bf . Thorax without punctures on sides 

 of disc except the usual one or two 

 setigerous punctures near margin ; 

 size larger Q. beevicornis, Thorns.' 



b. Antenna? dark with base testaceous ; legs 



testaceous, 

 a*. Thorax impressed at sides especially in 



male ; form broader ; antenna? stouter ; 



elytra usually briglit red Q. CEUENTUS, 01. 



b*. Thorax not impressed at sides ; form 



narrower ; antennaj more slender ; 



elytra always pitcliy black or brown . Q. XANTftOPUS, Er. 



c. Antenufe and legs entirely reddish tes- 

 taceous ; elytra red with postero-e.xternal 



angles darker ; size smaller Q. SCITUS, Grav. 



■ ii. Elytra witli distinct rows of punctures; inter. 



stices almost smooth Q. CINCTUS, Payk. 



{impressus, Panz.). 

 II. Thorax with only one or two dorsal punctures 

 on each side ; elytra red ; habitat exclusively in 

 ants' nests Q. brevis, TSr. 



The species belonging to this section vary considerably in general ap- 

 pearance ; with the exception of the Q. fulgidus group they do not present 

 any particular diflficulty ; this group, however^ has long been known as one 

 of the most difficult in the whole of our Staphylinida3, and as one concern- 

 ing which there is most difference of opinion ; Thomson (Skand. Col. 

 ix. p. 159, et seq.) describes as five separate species five insects which by 

 other authors have been considered races or varieties of Q. fidgidus, viz. 

 two with black elytra {Q. temporalis = mesomeli^ius, Marsh, and 

 Q. fageti), and three with red elytra {Q. quadripunctatus, Q. brevicornis, 

 and Q. imncticollis). The original Q. fulgidus of Fabricius had red 

 elytra (his description, Syst. El. ii. 596, is ^^ ater, nitidus, elgtris plan- 

 tisque testaceis, ano sub-ferrugineo'^), and is evidently identical with 

 Thomson's quadripunctatus, which has the apex of the hind body and 

 also the apex of the separate segments more or less reddish ; the best 

 plan, therefore, seems to be to limit Q. fulgidus to this form, which is the 

 commonest of those with red elytra ; Q. puncticolUs is evidently a dis- 

 tinct species by reaison of its smaller size, entirely black hind body, and 

 the punctuation of the thorax ; Q. brevicornis is larger and broader than 

 either of the preceding, with a larger head, and with the penultimate 

 joints of the antennae very transverse, and without punctures on the 

 sides of disc of thorax except the one or two usual large setigerous 



