ART. 17. LARVAE OF HOLARCTIC TIGER-BEETLES— HAMILTON. 61 



between the chitinized areas (fig. 117) ; median hooks with a single 

 prominent seta ; inner hooks about one-half the length of the median 

 hooks and with two fine, inconspicuous setae ; two of the large setae 

 cephalad of the mesal hooks and mesad of the distal half of the 

 median hooks usually forming a transverse or almost transverse row. 



Measurements — Length of larvae, 28 to 30 mm., width at the 

 third abdominal segment, 4 to 5 mm.; diameter of ocellus 2, 0.4(' 

 to 0.43 mm. ; distance between ocelli 1 and 2, 0.43 to 0.50 mm. ; length 

 of fronto-clypeo-labral area, 2.75 to 2.85 mm.; width, 2.45 to 2.55 

 mm. ; length of pronotum, 2.9 to 3.2 mm. ; width, 4 to 4.5 mm. 



This species is similar to Tetracha Carolina but can be separated 

 from it by its larger size, the absence of a distinct purple color to the 

 pronotum, the presence of a large number of secondary setae on the 

 membranous area of the abdomen, and the different arrangement of 

 the setae cephalad of the inner hooks and mesad of the distal half 

 of the median hooks. 



The larvae were collected at Southern Pines, North Carolina, by A. 

 H. Manee in sandy and gravely soil, clayey soil, and in moist, loose, 

 soil. They occurred in the same situations as Tetracha Carolina. 1 

 have collected larvae at College Park, Maryland, from clayey and 

 gravely soil along paths which were not frequently used. The open- 

 ings to the burrov.'s are about three-eighths of an inch in diameter, 

 the burrows are straight or slightly inclined from the vertical and 

 from 8 to 12 inches deep. 



3. Genus COLLYRIS Fabricius. 



Head with ridge on caudal part of frons U-shaped and not con- 

 tinuous with the ridge on the caudal part of vertex, U-shaped ridge 

 not prominent; latero-clypeus distinct, crescent-shaped; anterior 

 margin of the labrum narrow and rectangular; ocellus 1 about twice 

 the diameter of ocellus 2, ocelli 3 and 4 subequal in size and adjacent, 

 ocelli 5 and 6 wanting; antenna separated from the mandi])lc by a 

 narrow chitinized bar, the second segment not longer than the other 

 segments combined; maxilla with the ventral segment of the cardo 

 triangular, lacinia apparently absent, maxillary palpus two-seg- 

 mented, the distal segment slightly the longest, the proximal segment 

 without a spine on the latero-distal margin ; labio-stipites with a 

 slight furrow along the meson and without a carina on the lateral 

 and caudal margins, ligula not chitinized on the ventral aspect, 

 palpiger area with a single chitinized sclerite, labial palpus with 

 the proximal and distal segments subequal in length, the proximal 

 segment with two spinelike projections on its ventro-distal margin, 

 the proximal segment with three or four setae and the distal seg- 



