900 CHARLES PauL ALEXANDER 
two are eastern and two are western in their distribution. They include 
the largest and most beautiful species of the Limnobiinae. 
The European Pedicia rivosa (Linn.) was found by Beling (1879: 45-46) 
living in brooks and springs, or in wet spots among saturated leaves and 
other débris, sometimes associated with the larvae of Tzpula lutescens 
Fabr. The pupae live in cylindrical vertical burrows, clothed in the 
last larval skin, and are able to move up and down in these passages 
Pupation lasts from one to two weeks. 
Needham (1903: 285-286, and 1905:8) was the first to describe and 
figure the larva of the commonest eastern species, Pedicia albivitta Walk. 
Pedicia albivitta Walk. 
1848 Pedicia albivitta Walk. List Dipt. Brit. Mus., vol. 1, p. 37. 
Pedicia albivitta is a beautiful fly, common and widely distributed 
thruout the northeastern United States and Canada. The adults are 
on the wing in midsummer, and a few individuals may usually be found 
in June. The much rarer and more local P. contermina Walk. is a vernal 
species, on the wing in May and early June. 
The larvae of P. albivitta live in cold springs and beneath saturated 
moss at the edge of streams. The writer has never succeeded in rearing 
this species to the adult condition. 
Larva. — Length, 40-44 mm. 
Diameter, 5-5.5 mm. 
Color dark grayish brown above, paler at sutures and on posterior half of body; paler 
beneath, more grayish. 
Body covered with a short, appressed, dusky pubescence. Thoracic segments with a 
pencil of small setae on pleural region. Abdominal segments with a few delicate lateral 
setae on posterior ring, at about midlength of segments. Ventral creeping-welts on abdominal 
segments 4 to 7 completely divided on median line, the welts covered with a microscopic 
scurfiness. Spiracles (Plate LXI, 311) circular, separated by a distance about equal to 
diameter of one, situated on a slightly protuberant elevation. Spiracular lobes two, ventral 
in position, short, slender, each with about six setae ‘at tip. Anal gills (Plate LXI, 315) 
short, stout at base, before tip a constriction cutting off the elongate conical terminal 
segment, which is partly telescopic within the next basal segment. 
Head capsule (Plate LXI, 312) massive, elongate, as in this division. Labrum broadly 
transverse, lateral parts a little enlarged and projecting anteriorly into blunt lobes, with a 
long seta near inner margin; median region of labrum with two widely separated setae, Just 
laterad of each of which is a small papilla. Epipharynx roughened into a narrow transverse 
band of small spines. Mentum completely divided, each half continuous with ventral plate 
