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 Behng (1879:45-46) 

 living in brooks and springs, or in wet spots among saturated leaves and 

 other debris, sometimes associated with the larvae of Tipida 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 alhivitta Walk, 



Pedicia alhivitta Walk. 



1848 Pedicia alhivitta Walk. List Dipt. Brit. Mus., vol. 1, p. 37. 



Pedicia alhivitta 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. alhivitta 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 LXL 311) circular, separated by a distance about equal to 

 diameter of one, situated on a slightly protuberi'.nt 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 



