DEINOCERITES TETRASPATHUS 209 



Genitalia : Side-pieces over twice as long as wide, stout, a rounded conical 

 apical lobe on the inner angle bearing fine setse, a notch at middle of inner 

 margin bearing two short, very stout, blunt teeth and a stout spine within a 

 rounded prominence. Clasp segment small, stout, and chitinized like the side- 

 pieces, constricted near base, swollen apically, and bearing two equal terminal 

 claws in an apical notch, outer aspect densely clothed with fine hairs. Harpes 

 broad, rounded, outer margin furnished with a row of about twenty stout, fine 

 even teeth. Harpagones divided into three portions, the middle one with a row 

 of long teeth within, surrounding the middle portion, which has the tips pointed 

 and curved inward, not as long as the harpes ; outer portion very long, broad at 

 the base, tip rounded, reaching beyond lateral teeth of side-piece, smooth. 



Larva, Stage IV (plate 95, fig. 307). Head rounded, widest through middle 

 of sides, narrowed behind, a triangular, laterally projecting lobe beneath to 

 cover basal process of mandible ; antennae rather long, slender, a hair-tuft at the 

 middle ; upper head-hairs in fours, lower single and very long. Lateral comb of 

 eighth segment of many spines in a large triangular patch. Air-tube about five 

 times as long as wide, slightly uniformly tapering ; pecten of six teeth scattered 

 over the basal two-fifths of tube, followed by a long, two-haired tuft ; a smaller 

 tuft beyond apical third. Anal segment longer than wide, a rounded dorsal 

 plate, weakly chitinized and with indefinite lateral margin ; a smaller but more 

 sharply defined ventral plate between brush and base ; dorsal tuft of a long hair 

 and a multiple tuft on each side ; lateral hair single ; ventral brush large, con- 

 fined to the barred area. Anal gills in the form of two low, rounded prominences. 



The larvae live in the water in crab-holes and the adults rest in the upper 

 parts of the holes. Mr. Busck says : 



" It is identical in life-mode with the West Indian form and is found only 

 near the crab-holes in which the larvae live. During the day the adults remain 

 within the holes. They come out in a swarm, if a stick is inserted into the hole, 

 but return quickly to their hiding place when left alone. At dusk they come out 

 and swarm above the hole for copulation. Though a few specimens alighted on 

 my hand, which Was held close to the hole, when I disturbed the mosquitoes, 

 none attempted to bite, and I do not believe this species ever molests man." 



Mr. Jennings found the larvae associated with Culex extricator in crab-holes 

 along the shores, and also in holes from which posts had been withdrawn beside 

 a gravel-dump " simulated crab-holes." 



Panama, Atlantic and Pacific coasts. 



Bocas del Toro (W. H. Rosenau) ; Colon, July 20, 1907, associated with 

 Culex extricator (A. Busck) ; Caldera Island, Porto Bello Bay, March 21 and 

 June 1, 1908 (A. H. Jennings) ; La Boca, Canal Zone, June 12, 1907 (A. 

 Busck). 



DEINOCERITES TETRASPATHUS Dyar & Knab. 

 Deinocerites tetraspathus Dyar & Knab, Smiths. Misc. Colls., quart, iss., lil, 260, 1909. 

 Original Description of Deinocerites tetraspathus: 



Similar to D. cancer Theobald, but the cerci of the female with four terminal 

 flattened appendages instead of two; the appendages are not inserted together, but 

 are approximated towards the tip of the cercus. Second joint of the antennae about 

 fourteen times as long as wide, the succeeding joints about six times as long as wide 

 and subequal. Coloration as in D. cancer. 



Two females, Blueflelds, Nicaragua, and Puerto Barrios, Guatemala, without date 

 or collector label. 



Type no. 12109, U. S. N. M. 



Description of Female of Deinocerites tetraspathus (Male and Larva Unknown) : 

 Female. Proboscis rather long, slightly thickened towards apex; labellae 

 rather large, conical ; setae rather long, dense, those on labellae more prominently 

 14 



