286 Orthorrhapha brachycera. 



are two (pairs of) short, brown teeth, one above the other, and the 

 apex of the sheath is bent out and free (perhaps not natural); the 

 thorax has some short bristles above, and at its front margin there 

 are two very long, pointed spiracular tubes, almost as long as the 

 pupa ; the abdominal segments, except the first, have girdles of short, 

 brown splnes above; the last segment has two somewhat iarger spines 

 above, and two curved spines below. — The pupæ were found at 

 the shore, and rested in cocoons formed of sand and clay ; the author 

 says that the cocoon was smooth on the inside, no doubt there has 

 been a film as described under Dolichopus. The pupæ were found 

 on ^^/g and developed soon after. The pupa is further mentioned by 

 Brown (Entomologist VII, 1874, 207) and Smith (Proc. Entom. Soc. 

 London, 1874, p. XIX), but these papers I have not seen. 



The species of Machaerium occur exclusively at shores. 



Of the genus three species are known; one occurs in Denmark. 



1. M. maritimae Hal. 



1831. Hal. Zool. Journ. V, (1835), 352, 1, PI. XV, figs. 11—12. — 

 1850. Loew, Stett. ent. Zeitg. XI, 110, 13, Tab. I, Fig. 25 {BhapMum). — 

 1903. Kat. palåarkt. Dipt. II, 334. 



Male. Vertex and frons green. Epistoma broad, widening down- 

 wards, silvery whitish grey; palpi large, of the same colour. Occiput 

 green, a little greyish pruinose; postocular hairs black above, yellowish 

 below. Antennæ black, long, about twice as long as the head; the 



Fig. 89. Antenna of M. maritimae d". X 50, 



basal joints short, the third very long, thick at the base but excised 

 below so that the long apical part is thin; the arista much shorter 

 than the third joint. Thorax bright green or more golden green, with 

 two more golden or æneous stripes in the middle; it is somewhat 

 greyish pruinose, not much shining. Pleura green, slightly greyish 

 pruinose; propleura with pale hairs above, and with sorae black 

 bristles below, one of which is long. Abdoraen green or golden green 

 with some æneous or coppery reflexes, somewhat greyish pruinose; 

 it is clothed with short, black hairs, and has hindmarginal bristles, 



