Crane-flies 19 c 



The spiracles are very large and conspicuous, black. In some specimens there 

 are two black dots just above each spiracle and two somewhat similar dots 

 below the spiracles and on the ventral lobes; of these markings the ventral 

 dots are the most constant. Anal gills, four in number, blunt, fleshy. 



PtJP^. Male : Length, 18-23 mm. ; dorso-ventral depth, 3 • 8-4 mm. ; dextro- 

 sinistral width, 3-2 mm. Female: Length: 23 mm.; depth and width 4 mm. 



Male. (PI. V, fig. 50) : Colouration brown, the abdomen more yellowish 

 brown; the pleural membrane paler; the breathing-horns, appendages, and 

 sheaths dark brown; spines on the abdomen black. 



Antennal bases situated on a high crest, elevated above the level of the 

 breathing-horns. Pronotal breathing horns not conspicuous, short, directed 

 slightly forwards and shghtly divergent. On the pronotum a small knob 

 just before the breathing horns; on the prsescutum two widely separated tubercles 

 and just behind these but nearer the median line, two smaller tubercles, the 

 space^ between these tubercles connected by a row of crenulations. Leg-sheaths 

 reaching to the middle of the third abdominal segment; wing-sheaths reaching 

 the base of the second abdominal segment. 



Abdominal tergites: segments 1 and 2 with a small tubercle on the caudal 

 ring on either side of the median hne; segment 3 with two tubercles on either ■ 

 side, the inner one largest; segments 4 to 6 with three or four tubercles on either 

 side, the inner one largest; segment 7 narrowed, with two lateral spines and two 

 separated blunt tubercles; segment 8 narrowed, the lateral angles ending in 

 powerful tubercles with sharp points. Pleural integument coarsely punctured, 

 on the edge nearest the sternites with a single sharp spine on the caudal ring 

 of segment 1 and on segment 7 and two, one on each ring of segments 2 to 6. 

 Stermtes armed with circlets of powerful spines on the caudal ring, on segment 

 3 there being two, small and widely separated; on segments 4 to 7 there are 

 four such spines, larger and rather approximated. Segment 9 rounded, 

 indistinctly bifid, each side with a small, acute spine at the tip. 



Female. (PI. V, fig. 51) similar to the male above described, the sexual 

 differences being as follows: Sheaths of the tergal valves of the ovipositor 

 elongate, powerful, lying- parallel to one another, transversely wrinkled; sheaths 

 of the sternal valves of the ovipositor tiny, located at the apex of the eighth 

 segment. 



Mr. Johansen has recently called my attention to the description and 

 figures of the immature stages of this species by Dr. T. C. Nielsen.' As there 

 are some discrepancies between the descriptions and figures of the material 

 from northeast Greenland and that from the Canadian Northwest, it is possible 

 that more than one species is involved under the name of Tipula arctica. 



Stygeropis, possibly parrii (Kirby) . 



Locality: Melted ponds in the tundra at Demarcation point, Alaska, 

 May 1914 (F. Johansen). 



Two smaller specimens measure as follows: length, 20 to 24 mm.; diameter, 

 2-2 to 2-5 mm. 



A larger larva (No. 5a), length, 38 mm.; diameter, 3-7 mm. 



Form cylindrical, moderately elongated. Head-capsule with the antennae 

 long and slender, from three to four times as long as thick, cylindrical, yellowish. 



Chsetotaxy: Setae very weak and delicate, on the thoracic segments being 

 tiny lateral hairs. Abdominal tergites (PI. V, fig. 58) with no setae on the anterior 

 ring; on the posterior ring with the following bristles: a small lateral bristle 

 nearest the false suture; just before the caudal margin of the segment a more or 

 less impressed line, at its outer end with two or three bristles arising from 

 individual punctures; on either side of the reddish dorso-median vitta a prominent 



'' iThe Insects of the "Danmark" Expedition: Meddelelser om Gronland, vol. xliii, Copenhagen, 1910 

 pp. 57-9, PI, vii, figs. 1-7. 



Vo!. iii— 46963— 2J • 



