902 Charles Paul Alexander 



organic mud of the Staiulpipo Woods. One large larva was placed in 

 a watch crystal with a fully grown larva of Adelphomyia cayuga (supposi- 

 tion). It at once seized th(; latter in its mandibles at about the third 

 abdominal segment, and carried it helplessly all around the dish, 

 occasionally shaking it, quite as a terrier does a rat. 



Larva. — Length, 9.S mm. 



Diameter, 0.8 mm. 



Color, brown to orange-yellow on anterior segments of body, becoming darker on abdominal 

 segments due to the increase of pubescence. 



Body covered with an abundant, appressed pubescence. Form terete; body moderately 

 elongated, gradually narrowed toward both ends. Abdominal segments 2 to 8 divided 

 into a narrow basal ring and a much broader posterior ring; segments 4 to 7 with conspicuous 

 dorsal and ventral welts, which are larger and more conspicuous on posterior segments; 

 these welts occupying basal ring of segments, and bisected by a deep longitudinal median 

 impression, their surface covered with microscopic points. Thoracic segments before mid- 

 length with a transverse row of stiff, dark brown hairs grouped in tufts or pencils; these 

 hairs occurring on abdominal segments also, but less prominent here and occupying posterior 

 region of segments; pencils more numerous on ventral and pleural regions, much scantier 

 on dorsal surface except on pronotum. On sides of last abdominal segment, between spiracles 

 and spiracular lobes, several long setae arranged in a transverse row, lacking on mid-dorsal 

 and ventral regions. Spiracular disk (Plate LXII, 321) reduced to two ventral lobes, as in 

 this division, these lobes slightly united basally, not very elongate, blunt at their tips, which 

 bear about six dark setae. The two spiracles large and conspicuous, entirely exposed on 

 dorsum of last segment, separated by a distance a little less than diameter of one; middle 

 piece of spiracles large, black; ring brownish yellow. Anal gills four, long and slender, nearly 

 hyaline, divided into lobes by shght constrictions; posterior pair of lobes a little longer than 

 anterior pair. 



Head capsule elongate, flattened, massive, as in this tribe. Labrum conspicuous, exceed- 

 ing mentum and hypopharynx, the anterior margin fringed with long hairs. Mentum 

 (Plate LXII, 316) completely divided, each half with three subequal prominent teeth and 

 an additional much smaller lateral tooth; middle tooth of each side a little broader. Hypo- 

 pharynx (Plate LXII, 317) labriform, anterior margin deeply concave, roughened. Antenna 

 (Plate LXII, 3L8) short, the segment short-cylindrical, a little enlarged toward truncated 

 apex; at tip several papillae, of which two are exceedingly elongate, very slender, about twice 

 length of basal segment. Mandible (Plate LXII, 319) powerful, ending in an acute point; 

 ventral cutting edge with about four teeth, the basal one of which is the largest, subtruncate, 

 the next outer tooth a large, flattened, acute blade, two or three smaller flattened teeth just 

 before tip; dorsal cutting edge with about two small teeth. Maxilla (Plate LXII, 3-0) 

 short and very stout, the outer lobe much longer than the slightly smaller inner lobe. 



Pupa.' — (The following notes are taken from the cast pupal skins of the bred specimens. 



Labrum truncate. Labial lobes ovate. Maxillary palpi short and stout, broadest jupt 

 beyond base, tips blunt (Plate LXII, 322). Antenna moderate in length, tapering gradu 

 ally to tip. Pronotal breathing horn (Plate LXII, 323 and 324) short, cylindrical or 



