Xo. 64] DIPTERA OF COXXECTICUT : MORPHOLOGY 33 



elongated stipes, sti, a slender galea,* g^ and a maxillary palpus, nip^ 

 which may be composed of five segments in some primitive Diptera. 

 and is borne on a palpifer in such primitive forms as Tanyderim {pfr 

 of Fig. 2, H) and some female mosquitoes (Fig. 3, E), in which the 

 palpifer. pfr, has the appearance of a small vestigial segment of the 

 maxillary palpus. The so-called "lacinia" of certain Diptera, such 

 as Tabanus and Simuliurn^ is apparently homologous with the sclerite 

 labelled il (the interlorum) in the maxilla of the hymenopteron 

 Bracon liherator shown in Fig. 69, Plate 16, Vol. 31 of the Journal 

 N. Y. Ent. Society for 1923, and is connected with the hypopharynx 

 in all of these insects. 



The cardines, ca, are rather typically developed in many Ani- 

 sopodiae (Fig. 2, K), Trichoceridae** and Dixidae, and also in the 

 females of the Tabanidae. They are greatly developed in the Sim- 

 uliidae, but are not clearly distinguishable in most Diptera other than 

 these forms. The (Sardines are usually associated with the invagina- 

 tions of the posterior arms of the tentorium; but in the higher Dip- 

 tera the maxillae are no longer associated with the tentorial structures. 



The stipites, sti^ are slender in such primitive Diptera as Aniso- 

 pus (Fig. 2, K) ; but in such forms as Bittacamorpha (Fig. 2, A), they 

 are broader, and become approximated mesally in the anterior region. 

 In many asilids (Fig. 2, F) the stipites, sti^ merge mesally to form a 

 "zygostipes", zs, or composite plate, formed largely by the connected 

 stipites. In the mycetophilid Asyruhilum (Fig. 2, C), the stipital 

 plate is demarked into a median region, m^i, (which occupies the same 

 position as the mentum of certain other forms — mn of Fig. 2, E) and 

 two lateral regions, sti, which represent the stipites, so that the stipital 

 plate in such cases is probably formed by a combination of the stipites 

 with the mentum. In the higher Diptera, according to Peterson 

 (1916), the stipites gradually project more and more beneath the sur- 

 face of the proboscis, and finally become internal, apodeme-like*** 

 structures (cryptostipes), such as that labelled cr in Fig. 4, E and B 

 (here referred to as the maxillary apodeme or tendon). 



The galeae, g, are usually short in the primitive Diptera (Fig. 

 2, K), and, according to Hendel (1928), they close the sides of the 

 food channel formed by the labrum and hypopharynx in such lower 

 Diptera as BolffophiJa\nd Dladocia, etc. In some Nematocera, such 

 as the culicids (Fig. 3, E), they are cpiite long. In the tabanid Pati- 

 gonia lo7igirostris they are extremely long, and are also quite long in 

 such cyrtids as the one shown in Fig. 3, C. They are also well de- 

 veloped in such syrphids as the one shown in Fig. 4, B. The galeae 

 become rather short in most of the Cyclorrhapha, and are atrophied in 

 some of the higher forms (and in some of the Nematocera as well). 



*Rees and Ferris (1939) interpret the galea as a lacinia in Tipula, although the com- 

 parative studies of the maxillae bv Crampton (1923. Journal New York Ent. Society, 

 31, p. 77) indicate that the galea of the Diptera is homologous with the galea of 

 other insects. 

 **The character of the cardines and stipites of the Trichoceridae is essentially like 



that of the Anisopodidae and differs from that of the typical Tipuhdae. 

 ***Snodgrass (1935) calls these structures the rostral apodemes, and considers tnat 

 they are parts of the labrum, although Peterson (1916) regards them as parts of 

 the maxillary stipites. Thev are here designated as the maxillary apodemes since 

 they appear to be internal structures of the maxillae developed foi- nniscle attach- 

 ment. 



