WYEOMYIA HEMISAGNOSTA 159 



Male. — Similar to the female. Proboscis more distinctly swollen. Antennae 

 slender, the joints hardly shorter than in the female, with secondary subapical 

 hair-whorl ; hairs of whorls longer and more numerous. Abdomen expanded at 

 tip. Legs with a strong luster beneath ; mid tarsi with a white reflection be- 

 neath, strongest on second and third joints; last joint of hind tarsi white on 

 basal half beneath. Claw formula, 0.0-0.0-0.0. 



Length : Body about 3 mm. ; wing 3.5 mm. 



Genitalia (plate 5, fig. 30) : Side-pieces over twice as long as wide, tips coni- 

 cally tapered ; three long setje in a line near base ; basal lobes rounded trinagular, 

 setose. Clasp-filament with a long, slender stem, the tip expanded into a large 

 clasp, membranous, with setae on margin and in a row across disk; a supporting 

 corrugated median ridge ; outer lobe forming a spine-like support along margin 

 of middle lobe ; inner lobe truncate, forming a recurved angle of middle lobe. 

 Harpes narrow, thickened on inner margin, the tips curved and pointed. 

 Harpagones and unci forming basal cones. Basal appendages represented by 

 two stout setae on each side. 



Larva, Stage IV (plate 93, fig. 301). — Head rounded, with rounded angles 

 behind eyes; antennae moderate, uniform, a small two-haired tuft beyond the 

 middle; upper head hair-tufts in fours, lower in twos and long; ante-antennal 

 tufts in fours. Lateral abdominal hairs in fours on first segment, double on 

 second to sixth, single on seventh. Air-tube rather long, subfusif orm, tapering 

 most near tip, about five times as long as wide at base; terminal hooks moderate ; 

 with uniformly distributed long single hairs, only those nearest apex shorter 

 and doubled. Lateral comb of eighth segment of about twenty-three teeth in an 

 even, straight row, nowhere doubled, the teeth becoming smaller ventrally. Anal 

 segment longer than wide, with a large dorsal plate rounded laterally and reach- 

 ing well toward ventral line; dorsal tuft of two long hairs on each side; lateral 

 tuft on posterior margin of plate, of two long hairs; subventral tufts small, 

 multiple. Anal gills four, equal, about as long as the segment, their tips bluntly 

 rounded. 



The larvae live in water between the leaves of epiphytic Bromeliaceae. Mr. 

 Busck and Mr. Jennings both found the larvae in such situations. 



Panama. 



Boqueron Eiver, larvae in water between leaves of bromeliads. May 33, 1907 

 (A. Busck) ; Fort San Felipe, Porto Bello, January 31, 1908, larva in water 

 between leaves of bromeliads, associated with Orthopodomyia phyllozoa. 



We first described this species under Phoniomyia and again under Wyeomyia, 

 before having decided to unite these generic names. This unfortimate circum- 

 stance is additional proof of the undesirability of retaining genera founded upon 

 such unreliable characters as these were. Under Wyeomyia scotinomus we cited 

 a specimen from Tabernilla; but this we have now transferred to Wyeomyia 

 philophone. Under Wyeomyia dymodora we cited a specimen from Caldera 

 Island, which we have since made the type of Wyeomyia hapla, as further study 

 has revealed differences. 



WYEOMYIA HEMISAGNOSTA Dyar & Knab. 

 Wyeomyia hemisagnosta Dyar & Knab, Journ. N. Y. Ent. Soc, xiv, 227, 230, 1906. 

 Obiqinal Desceiption of Wyeomyia hemisagnosta: 



Allied to W. aporonoma D. & K., but entirely without the broad black margin ol 

 the anal plate; the subdorsal abdominal hairs are long in twos and threes, while they 

 are short, stellate tufts in aporonoma. They were collected by the junior author at 

 Sonsonate, Salvador, in cacao shells, associated with Aedes cyaneus and W. durhami 

 and at Port Limon, Costa Rica. 



