333 

 Geosargus viridis Say 



Sargus viridis Say, Jour. Acad. Nat. Sci. Phila., Vol. 3, 1823, p. 87. 



Larva and Pnparimn (PI. XLVIII, Fig. i6). — Length, 9 mm.; 

 width across dorsum at middle, 3 mm. Brownish testaceous, dorsal 

 surface with a dark grayish brown, slightly irregular, waved stripe 

 on each side of the middle line, the area laterad of the line occupied 

 by 2 rather less distinct stripes of the same color, which are slightly 

 fused and irregular, the whole dorsum having the appearance of being 

 six-striped, the median pair of stripes more or less distinctly connected 

 near anterior margin of each segment and enclosing 2 small spots near 

 posterior margin, the ventral surface similarly marked. Head with 

 only 2 brown dorsal lines ; tips of maxillary palpi, mandibles, and an- 

 tennal base dark brown. 



Head slightly longer than broad, armed as in Figure 8, Plate 

 XLVni; surface of thoracic and abdominal segments finely sha- 

 greened (Fig. 16, h), the armature as shown in the same figure; 

 spiracular depression in the form of a deep transverse slit, situated 

 very close to apex of segment; ventral segments with armature 

 similar to that of dorsal; apical ventral segment as in Figure 12. 



Described from examples obtained in cow manure at Muncie, III, 

 in April, 19 16. The larvae are very sluggish. The first example of 

 the imago emerged in the laboratory a month after being brought in 

 from the field. 



The species is common everywhere in Illinois, and in fact all over 

 the United States. 



Geosargus sp. ? 



I have before me a number of larvae of a species of Geosargus 

 that differ from viridis in having the head longer — more resembling 

 that of Microchrysa polita — and also in the striping of the dorsu.m, 

 the central dark stripe consisting of a series of diamond-shaped spots 

 — one on each segment — instead of a divided stripe as in viridis. In 

 other respects the larvae agree closely. 



I have a suspicion that the color of these specimens may not be 

 that of fully matured larvae, as they had previously undergone very 

 considerable changes, being whitish testaceous and without distinct 

 vittae and almost devoid of bristles when young, developing the vittae 

 and bristles as they matured. If they had overwintered safely they 

 might have assumed the coloring and structure which would have 

 proven them to be viridis, but as it is I can not definitely decide their 

 specific status. 



