4. NEMOTELUS 121 



Abdomen shining black witli a whitish yellow or orange spot on the middle 

 of the hindmargin of the second, third, and fourth segments, and these spots 

 though varying in width are almost equal in size ; sidemargins continuously 

 yellow or orange and connected along the hindmargin of the fifth segment, but 

 the sidemargins dilate near the hind corners of the second, third, and fourth 

 segments; sixth segment very small but with an obvious yellowish hind- 

 margin ; pubescence almost absent as it is so very short, sparse, and whitish 

 yellow ; ovipositor forming two small broad brown lamellae. Belly shining 

 black, with the foremargin of the second segment and the hindmargin of the 

 third and fourth segments obscurely yellowish ; sidemargins narrowly but 

 equally yellowish ; pubescence rather sparse, but imiversal and pale 

 yellow. 



Legs almost as in the male. 



Wings and halteres as in the male. Squamae yellow, with pale yellow 

 fringes. 



Length about 5-25 mm. 



This species varies within the usual limits of variation in the species 

 of Nemotelus, but may be distinguished from our other British species 

 without much difficulty. N. notatus has a shorter snout and whiter belly 

 in both sexes, and usually an isolated round black spot on the abdomen of 

 the male, while the female has the yellow sidemargins extended (even if 

 interruptedly) along the hindmargins ; N. pantherinus has the side markings 

 of the thorax much smaller and the belly much more white in the male, 

 and the female has no white spots on the frons ; individual specimens of 

 all these three species may sometimes be found with one or other of the 

 specific characters rather obscure, but in every case other specific characters 

 enable each specimen to be named with confidence. A male taken at 

 Aberlady on June 23, 1884, had evidently met with some injury to its head 

 in one of its earlier stages, as the head was reduced to practically only one 

 eye, which had a normal occipital inflation on each side on which was 

 the normal rather long pale brownish pubescence, and there was the usual 

 short adpressed forwards-pointing pale postocular pubescence; the proboscis 

 was rather thick, not geniculate, and with an apical outspread pair of large 

 (apparently) sucker-flaps. 



N. uliginosus is probably the commonest British species of the genus, 

 as it may occur anywhere in suitable marshy localities, especially salt 

 marshes. I have records from Sussex (Seaford), Kent (Gravesend and 

 Abbey Wood), Suffolk (numerous localities), Cambridgeshire (Burwell), 

 Lincolnshire (Sutton Wash), Merioneth (Barmouth), Kirkcudbrightshire 

 (Southerness), and Haddington (Aberlady), and though many of these 

 localities are on the coast yet some are far inland ; Duncan on the authority 

 of Haliday quoted it as common on Umhelliferce in Ireland. My dates 

 range from June 23 to September 16. Haliday gave its metamorphoses 

 (fig. 56) in detail in Nat. Hist. Eev., 1857, 194. It is recorded from 

 Northern and Middle Europe, though perhaps not from the extreme North 

 nor from South Europe. 



Synonymy.— Tho, original description of N. uliginosus was given by Linne in 

 Systema Naturae, ed. xii., 983, as follows : 



" 22. M. antennis clavatis mucronatis, abdominis dorso albo : segmentis duobus 

 " penultimis striga alba." 



" Habitat in Europa, /re^'z^jis uhi Triglochin crescit." 



"Corpus i/. domesticcB h minus. Caput nigrum f route flava. Antennae nigral. 

 " Thorax niger, nitidus : lateribus utrinqxie punctis 2 ohlongis alhis. Abdomen 

 " suhrotimdum, deiyressiusculum : dorso album s. luteum, basi media fuscum ; segmenfa 



