REVISION OP STREPSIPTERA — PIERCE. 



109 



Female. — Length of cephalothorax 0.82 mm., breadth of spiracles 

 0.96 mm., breadth at base of head 0.60 mm., distance between man- 

 dibles 0.15 mm. Cephalothorax light yellowish brown, with dark 

 brown band at base; broader than long, subtrapezoidal, squarely 

 truncate at apex; truncation over one-fourth the breadth at the 

 spiracles. Lateral margin very slightly convex. Mandibles rounded 

 with an outward curved tooth at apex. Spiracles slightly prominent 

 at sides. 



Triungulinid: Length of body 0.18 mm., length including stylets 

 0.22 mm., breadth of head 0.03 mm., greatest breadth 0.063 mm., 

 breadth of ninth abdominal segment 0.02 mm. 



Proportionate breadths of segments at broadest point: 



Head. 



Pro. 



Meso. 



Meta. 



1. 



2. 



3. 



22 



4. 



5. 



6. 



7. 



8. 



9. 



10. 



12 



14 



15 



19 



21 



22 



21 



20 



IS 



16 



14 



12 



8 



Proportionate lengths of segments on median line, dorsal: 



Head. 



Pro. 



Meso. 



Meta. 



1. 



2. 



3. 



4. 



5. 



6. 



7. 



8. 



9. 



10. 



S 



8 



5 



5 



3.5 



4.5 



3 



3.5 



3 



4 



2.5 



3 



4 



2 



This triungulinid was previously described by the writer with the 

 following characters: 



Head shorter than broad; eyes not prominent, consisting of several little blotches 

 of pigment; antennae very small, not as long as eyes are wide; mandibles short, 

 acuminate, about as long as eyes, immediately in front of eyes, not meeting at middle; 

 other mouth parts too small to recognize distinctly. Legs short, slender, weak, hardly 

 equaling in length the width of the prothorax; tibiae terminated by long, almost 

 invisible acuminate pad, which is strongly convex on the edge and almost equals in 

 length the tibiae. Body enlarging gradually to second abdominal and then narrow- 

 ing to the last segment, which is squarely truncate and terminated at each side by a 

 short tubercle, bearing a long, stout, acuminate stylet, which equals about six seg- 

 ments of the abdomen. Dorsum armed with many short stout spines at the apical 

 edge of each segment; venter armed with but few spines on each abdominal segment. 



Twenty-one hundred and fifty-two of these were actually counted as offspring of 

 one female (Pierce, 1904, 17). 



Type.— Cut. No. 10102, U.S.N.M. 



Named in honor of the writer's former associate, Myron H. Swenk, 

 who collected some of the specimens, and who has proven himself a 

 diligent worker on the Apoidea (pi. 4, fig. 9). 



31. STYLOPS VENTRICOS-iE, new species. 



Stylops melittx Nassonow, 1893 a. 



Host. — Andrena ventricosa Dours ; Europe (recorded definitely from 

 Fiume, Hungary, by Friese, 1893). 



Female. — Cephalothorax light yellowish brown with a dark band 

 extending convexly forward to the middle of the disk, but laterally 



