FAM. EMPIDIDZE 41 
6. S. Bigoti, Bezzi, Ann. Mus. Hungar, Vol. 2, p. 360 (1904), Vol. 1o, India. 
p. 456 (1912); Brunetti, Rec. Indian Mus. Vol. 9, p. 16 (1913); 
Fauna Brit. Ind. Dipt. Vol. 1, p. 329, pl. 4, f. 3 (1920). 
bicolor, Bigot (not Walker), Ann. Soc, Ent. France (6), Vol. 9, p. 127 
[1889] (Pterospylus) ; Bezzi, Ann. Mus. Hungar, Vol. 2, p 330 (1904). 
. S. curvineura, nov. sp. (1). Costa Rica. 
. S. curvipes, Fabricius, Syst. Ant. p. 147 [1805] (Damalis); Wiedemann, South America. 
Zool. Mag. Vol. 1, p. 1,60, pl. 2, f. 3[1817](Damalis) ; Aussereurop. 
Zweifl. Ins. Vol. 1, p. 537, pl. 4, f. 9 [1828] (Hybos); Bezzi, Nova 
Acta Akad. Naturf. Halle, Vol. 91 p. 314, note 2 (1909). 
9. S. debilis, Coquillett, Proc. U. S. Nat. Mus. Vol. 18, p. 436 (1895); S. and E. United States. 
Melander, Trans. Amer. Ent. Soc. Vol. 28, p. 253 (1902). 
10. S. dichelophorus, Bezzi, Ann. Mus. Hungar, Vol. 2, p. 330 (1904), Vol. 10, East Indies. 
p- 456 (1912). 
oo - 
II. S. dichogenus, nov. sp. (2). Costa Rica. 
12. S. dichrous, Bezzi, Nova Acta Akad. Naturf. Halle, Vol. gr, p. 318(1909). Bolivia. 
13. S. duplex, nov. sp. (3). Costa Rica. 
slender, and the distal three are close-set on distinct tubercles, hind tibia. somewhat clavate but otherwise simple, pubes- 
cence of legs conspicuous, hind metatarsi swollen and one-third aslong astheirtibize,. ^ Wings subhyaline somewhat dusky 
at apex, sections of costa nearly 5 : 2: 2 : 1, stigma beyond posterior crcssvein, large and completely filling end of marginal 
cell, second vein curving so that the submarginal cell is two-thirds the width of the marginal at base of stigma, last two 
sections of fourth vein subequal, of fiftn vein 1 : o.6. 
Three specimens, La Suiza de Turrialba, Costa Rica, Nov. 1922, Pablo Schild. 
Relate. to regletus Bezzi, but differs in that all coxae and the hind tarsi are black and the stigma is transversely limited 
within. 
(1) Syneches curvineura, nov. sp. — Length 3.5 mm. Closely related to S. longiventris, differing as follows : 
stigma larger, almost square, the marginal cell at the stigma two times as wide as the submarginal due to a pronounced 
curving of the second vein, veins thinner, wings subhyaline with cloudings about the anterior, posterior and anal crossveins; 
abdominal hairs relatively short and sparse, particularly on posterior portion of venter ; thorny bristles before hind knee 
better developed, three or four in number. 
Three males, three females, Turrialba, Costa Rica, April-August, Pablo Schild, in Melander collection. 
(2) Syneches dichogenus, nov. sp. — Male. Length 3.3- 4 mm. Occiput, knob of halteres and abdomen 
piceous, notum opaque blackish brown when viewed from in front, reddish brown but not cinereous when viewed from 
behind, antenne, mouthparts, legs, stem of halteres, and most of pleure yellowish, Upper facets much smaller than 
ocelli, palpi linear. Mesonotum hemispherical, posteriorly not excavated, its bristles small and black, pleure with more 
or less evident piceous spots above posterior coxe. Abdominal hairs small and sparse, valves terminal shining thin and 
forcipate. Leg bristles small and brownish, no inside bristle on middle tibia, the extensor bristle located at two-fifths length 
of middle tibia one-third as long as tibia, hind femora without dorsal bristles, with four small equidistant bristles on antero- 
flexor face, tarsi slender. Wings uniformly smoky, the long elliptical stigma somewhat darker and extending below ends 
of first and second veins, veins thin and blackish, third and fourth veins nearly parallel. 
Female. Mesonotum fuscous ; wings hyaline, veins brown, stigma faintly yellow. 
Eighteen males, fifteen females, received from P. Schild who collected them near Turrialba, Costa Rica, during July 
and August 1921. Typesin Melander collection. 
(3) Syneches duplex, nov. sp. — Male. Length 4.5 mm. Related to simplex and stigmaticalis in wing structure 
but differing in the larger size, larger ommatidia, shortened tarsi, the thickened and not slender hind tarsi and the more 
bristly hind femora. Piceous brown, including antennz, halteres and coxe, palpi slender and yellow, proboscis and legs 
brownish-yellow ; last joint of hind tarsi black. Upper facets nearly aslarge as ocelli. Thorax strongly convex, poste- 
riorly declivous, subshining, the declivity gray when viewed from behind, but two distant vittze, a triangular prescullar 
spot and supra-alar marks faintly gray when viewed from above and back, bristles and sparse hairs black. Abdomen darker 
apically, its basal long thin hairs yellowish to black, genitalia small and terminal, claspers bluntly triangular, not forcipate. 
Bristles and hairs of legs pronounced, four equidistant extensor bristles on front tibize, extensor bristle at two-fifths of 
middle tibiae and about one-half length of tibia, a shorter preapical bristle, postero-extensor row of four bristles on middle 
tibie, middle femora with about eight bristles in each flexor row, hind femora with three stiff bristles on upper posterior face 
toward knee, with a rowof six bristles beneath and with shorter flexor bristles, hind tibiz with long extensor bristles at 
middle and before apex, hind tarsi robust, the metatarsus with closely pubescent sole and with five black spines on posterior 
face, third and fourth joints broader than long. "Wingslightly brownish, veins brownish yellow, a diffused quadrate stigmal 
