
704 THE AMERICAN NATURALIST. [VoL. XXXVI. 
Bibiocephala doanei! Kellogg (Figs. 24-26). — The Blepha- 
roceride, or net-winged midges, agree with the Simulidz, or 
black flies, in having the females equipped with mandibles, 
which in the Blepharoceridze are well developed as long, slender, 
bladelike saws (see Fig. 24, md.) used to lacerate the bodies (as 
I have observed) of the tiny midges caught as prey by the 
bloodthirsty females. In addition the adult females have max- 
illae (Fig. 24, mx.) with well-developed lobe (mx./.) and long 
five-segmented palpus (mzx..), and a labium (/Z) consisting of 
strong elongate basal sclerite which presents indications of a 
line of fusion of submentum and mentum, and a pair of free 
fleshy terminal lobes, the paraglosse (pfg.). The males are 
equipped like the females except for the mandibles. 
The larva of Bibiocephala doanez has a biting mouth (Fig. 25) 
composed of short, stout, crushing mandibles (md.), weaker 
jawlike maxillae (#x.) without palpi, and a soft liplike labium 
(lij. In addition there are well-developed labrum-epipharynx 
(Z.ep.) and hypopharynx (Zy5.). 
The development of the imaginal head shows the same phe- 
nomena as in Simulium. In Fig. 26, from a vertical transverse 
section through the head of an old larva, the derm of the form- 
ing imaginal head is plainly seen in continuous layer, modified 
at z.c. to produce the developing compound eyes and at mx. and 
md. the forming imaginal mandibles and maxilla. In this 
section the imaginal parts of the maxille visible are the 
forming palpi, and their definitive, long, segmented condition 
is plainly to be seen in these telescoped organs tucked tightly 
inside the larval maxilla. The forming mandibles do not yet 
show their definitive character, but in tracing these organs 
through a series of older larva: the gradual taking-on of the 
slender sawlike character is manifest. The series of Blepha- 
rocera preparations which I have show even more plainly than 
the Simulium preparations the perfect correspondence and 
* box-in-box " sort of relation which exists between the larval 
1 This blepharocerid fly was described by me in Psyche, vol. ix (April, 1900)» 
PP. 39-41, 2 figs., under the name Lifoneura doanei. In a recent revision of the 
North American Blepharoceridz, now in press, I refer this species to the genus 
Bibiocephala. 
