52 Orthorrhapha brachycera. 



a little shorter in the female than in the male; the basal joint is 

 hairy above, in the male of latipennis it has bristles ; the second joint 

 overlaps the third a little in a dififerent way in the various species, it 

 has shorter or longer bristles at the apex; the arista is dorsal, shorter 

 or longer, and has the basal joint of some length; it is short-haired. 

 Epistoma moderately broad, somewhat or slightly broader in the 

 female. Glypeus is slightly marked ofif, a little arched, it reaches to 

 the lower margin of the eyes, or a little longer, and it is longer in 

 the male than in the female; in the female of latipennis it does not 

 quite reach the lower margin of the eyes; this character, that the clypeus 

 reaches so far down, is the chief character, and almost the sole 

 separating the genus from BoUchopus, and the character is rather 

 small, as at least one species, B. iaticola Verr. comes very near to 

 Hygroceleuthus in this respect. The oral aperture and the proboscis 

 are a little larger in the female than in the male. Thorax has six 

 dorsocentral bristles, two posthumeral, a præsutural, three supraalar, 

 a postalar and two notopleural bristles. Scutellum slightly hairy. 

 The legs are somewhat bristly, and hind metatarsus has bristles above; 

 it is of about equal length with the second joint. In a foreign species, 

 the American H. latipes, the middle tarsi have the four last joints 

 dilated. The wings are in some species {latipennis and the non- 

 Danish rotundipennis) broad, especially in the male; costa with a 

 larger or smaller swelling at the apex of the subcostal vein in the 

 male; the anal vein reaches near to the margin. 



Of the developmental stages I have examined a pupa of H. lati- 

 pennis. It is 6 mm long, yellow^ ; the sheaths of the antennæ lie down 

 the front side of the head, diverging with the apices; at the base of 

 each is a small, flat tooth, the two teeth forming together a trans- 

 verse edge with two small, black points in the middle; at the middle 

 of each sheath is a small, transverse, serrated tooth, with a hair at 

 the inner end; on the front side of the head and on thorax are a 

 few other, small hairs. At the anterior margin of thorax are two 

 moderately long, slightly curved, attenuated spiracular tubes, they are 

 brown, black in the apical half. The abdominal segments have each, 

 except the first, a dorsal girdle of densely placed, short, flat, brown 

 spines. The sheaths of the legs reach to the end of abdomen. The 

 pupa was found, together with the cast larval skin, below decaying 

 sea-weed on the shore on '-"/s, and it developed on ^^k. The larva 

 thus evidently lives on the shore below sea-weed. 



The species of Hygroceleuthus occur on sea-coasts. 



As said the genus is in all essential respects similar to Dolichopus, 

 and the main distinguishing character, that the clypeus reaches so 



