Pupa, cCr. o/'Orplmcpliila (estacca. 633 



the living larva is translated from Thienemann's paper, since 

 only preserved material is available for this study : — 



"Length of full-grown larva 14 mm., width about 

 1 mm. Number of segments, head+ 12 segments. General 

 appearance that of a Chirouomid larva. Colour : venter 

 white. Dorsum and pleurse whitish green, marbled with 

 dark grey-green. In the young larvte the light tones 

 predominate ; those about to pupate are much darker. 

 Segments 1 and 2 are darker than the rest ; the light 

 marbling first developes in segment 3. Chaetse black. 

 Head light reddish brown, bent strongly downwards/' 



Head. — Complete ; well chitinised ; bent ventrally at a 

 sharp angle, resembling in this respect Forcipomyia and 

 Atnchopogon, Ceratopogonines (Malloch, 1915). A unique 

 condition exists in the presence of three pairs of cone-like 

 protuberances and a median, unpaired, trilobed protuberance 

 of the chitinous capsule of the head (text-fig. 1,1. & II., 

 A, Bj C, D). These all point in an antero- ventral direction. 

 The protuberance C contains the pigment of the eye-spot., 

 and its surface is slightly modified to form a rudimentary 

 lens. The antennce consist each of a sensory ring accom- 

 panied by a group of three minute finger-hke processes 

 situated in a membranous area on the top of a cylindrical, 

 obliquely truncated protuberance (PI. VII. fig. 5, and an^ text- 

 fig. 1) on either side of the frons, in practically the same 

 position as in Forcypomyia. 



Chcetotaxy : twelve pairs of chsetse occur upon the head, 

 arbitrarily numbered 1-12, and two pairs of sensory pits, 

 13 and 14. Chsetse numbers 1, 2, 3, and 5 are stout and 

 strong at the base, but at a point rather less than half their 

 length they flatten and split into a number of hairs, usually 

 four. The other chsetse of the head are simple ; at 10, two 

 hairs arise from a common opening in the chitin. 



The frontal and clypeal sutures are distinct througliout 

 their length, and, though no actual transverse suture divides 

 the frons from the clypeus, the latter separates very readily 

 during dissection at the point indicated by a dotted line in 

 text-fig. 1, 1., and PI. "STII. fig. 11. Prom this point, just out- 

 side the cly})eal suture, a very strong inner thickening of the 

 wall of the head extends forward to fuse with the thickened 

 ring surrounding the mouth-parts, and to send off a strong 

 inner projection which serves as fulcrum for the mandible. 



Mouth-parts.—Lahrum (PI. VIII. figs. 11, 12): the form 

 of the labrum is quite distinct from that of any other 

 Nematocerous larva. A narrow band of chitin passes along 

 the dorsum from the anterior margin of the clypeus, and 



Ann. (t- Moq. N. Hist, Ser. 9. Vol. xi. 41 



