ART. 17. LARVAE OF HOLARCTIC TIGER-BEETLES HAMILTON. 37 



Two distinct sizes were found among the larvae in autumn, wliich corre- 

 sponded to tlie first and second year of venusta, so that it seems highly prob- 

 able that the larval life lasts two years, while that of the adult continues for 

 about eleven months. 



CICINDELA SILVICOLA LatreiJlc. 



Figs. 159, 170, and ISO. 



Heitter, E., two larvae in the collection of the U. S. National Museum. 

 Bought from and determined by Reitter, 1922. 



Color. — Head and pronotiim brownish bronze with a purple re- 

 flection, lateral margins of pronotum slightly lighter ; setae on dorsal 

 aspect of head and pronotum white, the other setae brown. 



Head. — Setae on dorsal aspect long and conspicuous; diameter of 

 ocellus 2 slightly less than the distance between ocelli 1 and 2; 

 fronto-clypeo-labral area slightly wider than long; U-shaped ridge 

 on caudal part of frons bearing tAvo prominent setae; antenna with 

 the proximal and second segments subequal in length, the third 

 three-fourths and the fourth one-half the length of the second, the 

 proximal segment with 5 to 7 setae and the second with 9 or 10; 

 maxilla with the proximal segment of the galea bearing 3 setae on 

 its mesal margin, maxillary palpus three-segmented; ligula with 4 

 fine setae on its ventro-distal end arranged in a transverse row, proxi- 

 mal segment of the labial palpus with 3 spinelike projections on the 

 ventro distal margin and with 2 setae on each side of these spines, 

 the proximal segment with 4 setae and the distal segment with one. 



Thorax. — Pronotum with the cephalo-lateral angles extending as 

 far cephalad as the cephalo-mesal portion, lateral margins slightly 

 carinate; primary setae long and prominent, secondary setae ab- 

 sent except for a single prominent one on each cephalo-lateral part of 

 the pronotum (fig. 159). 



Abdomen. — CJiitini/ed areas distinct; secondary setae few, short, 

 and not conspicuous (fig. 170) ; ninth abdominal sternum with the 

 caudal margin bearing two groups of four setae each ; median hooks 

 with three or four setae; inner hooks normally with two but some- 

 times three setae, the spinelike projection one-half the length of the 

 hook (fig. 180). 



Measurements. — Length of larvae, 18 to 20 mm.; width at the 

 third abdominal segment, 2 to 2.5 mm.; diameter of ocellus, 2, 0.30 

 to 0.32 mm. ; distance between ocelli 1 and 2, 0.40 to 0.42 mm. ; length 

 of fronto-clypeo-labral area, 2.7 mm.; width, 2.7 mm.; length of 

 pronotum, 2.5 mm. ; width, 4.4 mm. 



Remarks. — This is an European species, the larvae of which were 

 purchased from E. Reitter, Paskau, by the U. S. National Museum. 

 No data accompanied the material. 



