160 MOSQUITOES OF NORTH AMERICA 



The following is an abstract of the table : 



1. Anal processes equally developed 3 



3. Lateral comb of the eighth segment of many teeth in a long line. . 4 



4. Comb of teeth in a band, at least in part two rows deep 7 



7. Tube without false pecten 9 



9. Tube straight, tapered only near the tip 10 



10. Tube and plate without black ring; subventral tuft long hemisagnosta 



Desckiption of Laeva of Wyeomyia hemisagnosta (Adult Unknown) : 



Larva, Stage IV (plate 93, fig. 303). Head rounded, widest through eyes, 

 oblique on sides, a small notch at insertion of antennae, front margin arcuate. 

 Antennae small and slender, mth a minute hair at outer fourth ; four irregular 

 spines and a digit on a long pedestal. Head-hairs single and slight. Mental 

 plate narrow, triangular, with a prominent central tooth and eleven on each side, 

 basal ones more remote, last one small. Mandible quadrangular, with a group 

 of spines near base; a filament before tip; an outer row of cilia from a collar; 

 a row of slender processes on outer margin with deeply divided tips; dentition 

 of four teeth on a process, the first the longest ; two spines before, a long filament 

 and a row of thick hairs with divided tips within ; process below long, taking the 

 place of the basal angle, shortly furcate, with a row of hairs along margin and a 

 tuft at tip of each limb ; a row of stout hairs within and another at base. Maxilla 

 irregularly hemispherical ; a row of short, stout spines on inner margin, the 

 whole half densely hairy; a tuft of long hairs at tip, with a long articulated 

 spine ; a row of hairs running down toward base of palpus, with a filament near 

 the middle. Palpus small and stout, with four minute digits. Thorax quadrate, 

 wider than long; abdomen moderate, anterior segment shorter; lateral hairs in 

 fours on first two segments, in twos on third to fifth, single on sixth and seventh. 

 Air-tube slightly tapered, three times as long as wide, with two rows of sparse 

 single hairs, the basal posterior one double. Lateral comb of eighth segment a 

 long band of spines, single above, double and smaller medianly and below; 

 single spine simple and thorn-shaped or widened at tip, with a fringe of spinules. 

 Anal segment as long as wide, with a dorsal plate reaching well down the sides ; 

 dorsal tuft of long hairs on each side ; two long lateral hairs ; subventral stellate 

 tufts longer than the segment. Anal gills stout, subequal, bluntly rounded. 



The larvas live in the water collected in cocoanut-shells and similar locations, 

 probably also in bamboo-joints or hollow trees. 



Central America. 



Sonsonate, Salvador, August 30, 1905, larvae in cocoanut-husks on a planta- 

 tion just out of town (F. Knab) . 



The original culture from which these larvae were obtained contained numer- 

 ous other larvae, Wyeomyia aporonoma, Limatus cacophrades, Hcemagogus albo- 

 maculatus, and Megarliinus moctezuma, and adults were not obtained of this 

 species. We have not since obtained specimens that we could associate with 

 them. In our original description we cite also the locality Port Limon, Costa 

 Rica, which may be correct, as we have a note of comparing a larval skin from 

 that place taken from cacao-shells, but have at present omitted the locality, as 

 the original dra^vdng was not made from that specimen. 



Genus PROSOPOLEPIS Lutz. 



Prosopolepis Lutz, Imprensa Medica, 312, 1905. 

 Prosopolepis Peryassu. Os Culicid. do Brazil, 38, 1908. 

 Prosopolepis Dyar & Knab, Proc. U. S. Nat. Mus., xxxv, 65, 1908. 

 Prosopolepis Theobald, Mon. Culic, v, 574, 594, 1910. 



The type species of Prosopolepis Lutz is Prosopolepis confusus Lutz. 



