The Biology of the North American 
Crane-Flies 
(Tipulidae, Diptera) 
VI. The Genus Cladura Osten Sacken 
By CHARLES P. ALEXANDER 
Generic Diagnosis 
Larva. Form comparatively short and stout; integument 
provided with a delicate appressed pubescence; no distinct setae; 
basal annulus of each of abdominal segments two to seven with a 
transverse area of microscopic points arranged in long, transverse 
rows. Last ventral segment with a fiattened lobe covered with 
short setae, evidently an organ for shoving. Spiracular disk 
entirely without lobes, the spiracles being situated on the exposed 
dorso-caudal surface of the last abdominal segment. Head-capsule 
relatively compact; frontal plate broad, only slightly narrowed 
behind. Labrum quadrate, with conspicuous, oval, lateral arms; 
antennae two-segmented, the terminal segment elongate-oval; 
mandibles of a herbivorous type, with an apical point and two 
incomplete rows of teeth on the inner or cutting face; mental bars 
widely separated, each bar provided with two acute teeth at its 
mesal end. 
Pupa. Cephalic crest gibbous, entire or feebly bifid, armed 
on either side with a single powerful bristle; two bristles on both 
the front and vertex; labrum with pair of small bristles at each 
cephalic-lateral angle; labial lobes subquadrate, weakly separated 
by the apex of the labral sheath; palpal sheaths short and stout, 
straight; lateral margins of eye produced laterad into a digitiform 
lobe; antennal sheaths extending to opposite one-third the wing- 
sheaths. Pronotal breathing horns lacking, entirely sessile; pro- 
notum and mesonotum armed with conspicuous bristles; wing- 
sheaths ending opposite the base of the third abdominal segment; 
leg-sheaths long, ending opposite the base of the sixth abdominal 
segment, the hind legs longest, the middle legs shortest. Abdominal 
tergites with ten strong bristles, eight being arranged in a single 
transverse row along the posterior margin; abdominal pleurites 
with four strong bristles, one on anterior ring, two near the caudal 
margin of the posterior ring, one ventrad of the spiracle; spiracles 
rudimentary, situated on segments two to seven; sternites unarmed 
with bristles. . 
Discussion of the Genus 
The genus Cladura was erected by Osten Sacken in 1859 
(Proc. Acad. Nat. Sci. Phila., p. 229). The genus includes but six 
