respiratory organ; pupa normally lying on its side 

 nearly motionless in an arched position (fig. 14:1 8^) 

 DIXIDAE 



— Swimming paddles absent (f.ig. 14:416-tf), or if present, 

 provided with hairs or spines (figs. 14:22A; 14:31/), 

 or pupa differing in other characters 15 



15. Prothoracic respiratory organs without open stigmata, 

 or composed of numerous filaments (figs. 14:31;'; 

 14:35c), or absent TENDIPEDEDAE (part) 



— Prothoracic respiratory organs with open stigmata 

 (figs. 14:226; 14:39Z-?, u,v,hh) 16 



16. Anal segment with a 2-lobed swimming paddle 



TENDIPEDID AE (part) 



— Anal segment ending in a pair of pointed processes 

 (figs. 14:416-d; 14:42o-<) HELEIDAE 



17. Pupa robust, short, with greatly elongated prothoracic 

 respiratory organs (fig. 14:49c, },m, q,u) 



DOLICHOPODIDAE 



— Pupa more elongate, prothoracic respiratory organs 

 not so conspicuous 18 



18. Prothorax with a large aperture mesad of, and connected 

 with, the spiracle (fig. 14:48/) TABANIDAE 



— Prothorax without such an aperture EMPIDTDAE 



19. Puparium within last larval skin, which is unchanged 

 in shape; larval head capsule distinct (fig. 14:45) 



STRATIOMYIDAE 



— Puparium without distinct head, the larval skin modi- 

 fied in shape owing to the changed form of pupa within 

 (figs. 14:52c; 14:53c, of; 14:586; 14:596; 14:60c; 14:63c, 

 K),<l, s ) (CYCLORRHAPHA) go to couplet 20 of larval 

 key for characters of spiracles or pharyngeal skeleton 

 which remain on the surface of the puparium. 



GENERAL DIPTERA REFERENCES 



ed., Cambridge, 



BRUES, C. T., and A. L. MELANDER 

 1954. Classification of insects. Rev. 

 Mass. 917 pp. 

 CHU, H. F. 



1949. How to know the immature insects. Dubuque, 

 Iowa. 234 pp. 

 CRAMPTON, G. C. 



1942. The external morphology of the Diptera./n Insects 

 of Conn. Pt. VI. Diptera, fasc. 1. Bull. Conn. Geol. 

 Nat. Hist. Surv., 64, pp. 10-165. 

 CRISP, G., and L. LLOYD 



1954. The community of insects in a patch of woodland 

 mud. Trans. Roy. Ent. Soc. London, 105:269-314, 3 pis. 

 CURRAN, C. H. 



1934. The families and genera of North American Diptera. 



New York. 512 pp. 

 1942. Key to families. In Insects of Conn. Pt. VI. 

 Diptera, fasc. 1. Bull. Conn. Geol. Nat. Hist. Surv., 

 64 pp. 175-182. 

 FRIEND, R. B. 



1942. Taxonomy. Wing 

 Pt. VI. Diptera, fasc. 

 Surv., 64, pp. 166-174. 

 HENDEL, F. 



1928. Die Tierwelt Deutschlands. 11. Teil. Zweiflugler 

 order Diptera n. Allgemeiner Teil. Jena. 135 pp. 

 IIENNIG, W. 



1948-1952. Die Larvenformen der Dipteren. 1 Teil, 

 186 pp. 2 Teil, 458 pp. 3 Teil, 628 pp. Berlin. 

 JOHANNSEN, O. A. 



1934. Aquatic Diptera. Part I. Nemocera, exclusive of 

 Chironomidae and Ceratopogonidae. Mem. 164, Cornell 

 Univ. Agric. Exp. Sta., 71 pp., 24 pis. 



1935. Aquatic Diptera. Part H. Orthorrhapha-Brachycera 

 and Cyclorrhapha. Mem. 177, Cornell Univ. Agric. 

 Exp. Sta., 62 pp., 12 pis. 



1937. Aquatic Diptera. Part IH. Chironomidae: sub- 

 families Tanypodinae, Diamesinae, and Orthocladiinae. 

 Mem. 205, Cornell Univ. Agric. Exp. Sta., 84 pp., 

 18 pis. 



venation. In Insects of 

 1. Bull. Conn. Geol. Nat. 



Conn. 

 Hist. 



377 

 Wirth and Stone: Diptera 



1038. Aquatic Diptera. Part IV. Chironomidae: subfamily 

 Chironominae. Mem. 210, Cornell L'niv. \ l tm . Exp. 

 Sta., pp. 1-56, pis. 1-9. 

 MALLOCH, J. R. 



1917. A preliminary classification of Diptora, exclusive 



of Pupipara, based upon larval and pupal c-hariu tol , 



with koys to imagines in certain families. Part I. 



Bull. Illinois Lab. Nat. Hist., 12:161-409, 29 pis. 



NEEDHAM, J. G., and C. BETTEN 



1901. Aquatic insects in the Adirondacks. Bull. N.Y. 

 St. Mus., 47:383-612. 

 PETERSON, A. 



1951. Larvae of insects. Coleoptera, Diptera, Neuroptera, 

 Siphonaptera, Mecoptera, Trichoptera. Part II. 4 16 pp. 

 Columbus, Ohio. 

 TORRE-BUENO, J. R. DE LA 



1937. A glossary of entomology. 336 pp., 9 pis., Brooklyn, 

 New York. 

 WALTON, W. R. 



1909. An illustrated glossary of chaetotaxy and ana- 

 tomical terms used in describing Diptera. Ent. News, 

 20:307-319, 4 pis. 



Family TIPULIDAE 



The family of true crane flies is very large, and the 

 members are rather diverse in size and form, distin- 

 guished, in addition to the general crane fly facies, 

 (fig. 14:3a), by the well-developed V-suture, lack of 

 ocelli, and presence of two anal veins reaching the 

 wing margin. The legs break off very readily between 

 the trochanter and femur and are used very awkwardly 



Fig. 14:3. Tipula trivittaia Say. o, adult female; b, larva; 

 c, pupa (Alexander, in Curran, 1934). 



