64 MISC. PUBLICATION 42 4, U. S. DEPT. OF AGRICULTURE 



Adult female. — Elongate, lateral margins nearly parallel, somewhat constricted 

 near posterior end ; 1 mm. long, 0.45 wide. 



Margin : 8-shaped pores in a single row terminating near posterior con- 

 striction or six or seven times a posterior pore's length from bases of apical 

 setae, anterior and posterior pores largest, one 12 /x long and 8 wide, the majority 

 around 8 \x long and 5 or 6 wide, varying in size on lateral margins with the 

 smallest 6 /x long and 4 wide, axes of pores transverse, longitudinal or diagonal 

 to body margin, usually twice a pore's length apart ; quinquelocular pores ventrad 

 of 8-shaped pores in a single or double row near posterior end, and in a row 

 2-6 pores wide elsewhere, terminating at the posterior pair of 8-shaped pores 

 or 3 8-shaped pores from it, also in a double row dorsad of 8-shaped pores, 

 terminating at posterior third, the rows either distinct or interspersed among 

 the 8-shaped pores ; disk pores in a fairly regular row in the ventral row of 

 quinquelocular pores, and in an irregular row in the dorsal row of quinque- 

 locular pores, both rows of disk pores terminating slightly more than the length 

 of an apical seta from bases of setae. 



Dorsal surface : Both large and minute 8-shaped pores absent ; disk pores 

 fairly numerous ; tubular ducts 28 /x long ; dorsal tubes present. 



Ventral surface: Antenna stout thimble-shaped, with 2 setae slightly shorter 

 and 1 much shorter than diameter of antenna ; beak without setae ; spiracle 

 with bar rather broad, with atrium large and with opening very large, quin- 

 quelocular pores in atrium and extending over edge of opening to marginal row 

 of quinquelocular pores, around 20 pores in and on edge of spiracle, around 10 

 or 12 outside opening of anterior spiracle in a band 5 or 6 pores wide, giving 

 the appearance of a widening of marginal row rather than that of a splracular 

 row extending to body margin ; posterior spiracle opening directly into marginal 

 row of quinquelocular pores ; 8-shaped pores 5 fx long- and 4 wide, scattered on 

 anterior half of body and concentrated between mouth parts and posterior 

 spiracles ; dark-rimmed 8-shaped pores observed only on abdomen, arranged in 

 a fairly definite single and double row from posterior spiracles to near penulti- 

 mate pair of marginal 8-shaped pores, and tending toward distribution in 2 

 or 3 sparse transverse rows in lateral area ; submarginal 8-shaped pores appar- 

 ently absent, the only indication of a submarginal row being the dark-rimmed 

 8-shaped pores in lateral area ; 6 pairs of submarginal setae posterior to posterior 

 spiracles, the posterior pair nearer to the posterior pair of marginal 8-shaped 

 pores than to the apical setae; 1 pair of setae posterior to genital opening, 1 

 pair anterior to opening, and 2 additional pairs placed at uniform intervals 

 anterior to the latter. 



Apex of abdomen : Setae, apical 5.4 /x long, outer ventral 3 /x long ; anal opening 

 in margin, circular ; anal tube small at opening, greatly enlarged near center, 

 smaller at inner end, heavily sclerotized on outer half, and slightly sclerotized 

 on inner end ; anal ring a sclerotized, circular band, with 2 setae apparently 

 2.7 ix long. 



Second stage. — Resembling adult female in shape but without constriction 

 near posterior end ; margin with quinquelocular pores in a single row only 

 ventrad of 8-shaped pores, disk pores very sparse, all ventrad of 8-shaped pores ; 

 ventral surface with atrium of spiracle slightly enlarged and with 3-5 quinque- 

 locular pores in atrium and extending to body margin, large 8-shaped pores less 

 numerous but in same relative position as in adult, dark-rimmed 8-shaped pores 

 very sparse, setae not observed, possibly owing to poor condition of specimen ; 

 apex of abdomen with apical and ventral setae broken, anal tube shorter than 

 in adult, anal opening, anal ring, and ring setae as in adult. 



Third-stage male. — Resembling adult female in shape and size but without 

 constriction near posterior end ; margin with 8-shaped pores much less numerous 

 than in adult female, only 2 or 3 at anterior end and 1 in lateral area, quinque- 

 locular pores in a single row ventrad of 8-shaped pores, terminating before the 

 8-shaped pores, disk pores sparse and in a definite row only near posterior end; 

 dorsal surface with a semicircular submarginal row of 7 or 8 8-shaped pores near 

 anterior margin, which are one-third larger than posterior marginal 8-shaped 

 pores ; ventral surface with 4 pores in spiracle and 3 or 4 outside spiracular 

 opening, large 8-shaped pores somewhat smaller in comparison to marginal 

 than in female, legs represented by 3 pairs of circular, slightly sclerotized areas, 

 apparently without claws, apparently without dark-rimmed 8-shaped pores but 

 with submarginal (possibly actually dark-rimmed) 8-shaped pores in a single 

 row on posterior half of body, terminating at the posterior pair of marginal 

 8-shaped pores and as numerous as corresponding marginal 8-shaped pores, 

 setae present in median area ; apex of abdomen with apical setae minute, anal 

 tube apparently sclerotized throughout, no ring setae observed. 



