50 [March, 



The pupa (figs. 1 and 2) is yellow and shining, with a little 

 horn at the base of the wing-covering, and a peculiar projection 

 on each side of the anterior margin of the disc of the thorax, which, 

 when the pupa is alive, tapers from apex to base, as shown in fig. 1, but 

 after the insect has emerged, its base shrivels, leaving an almost 

 orbicular ball at its apex. The pupa never entirely casts off the skin 

 of the larva, but retains it at the base of the fifth segment. The fly 

 emerges usually early in the morning, and soon dies. All my speci- 

 mens are decidedly dull and not " rather shining," as described by 

 Mr. Theobald.* 



Everton House, Tpswicli : 

 January, 1897. 



ON THE USE OF THE TERM TEGULA IN DIPTERA. 

 BY D. SHARP, M.A., F R.S., &c. 



Dr. Meade is quite right in protesting against the use of the term 

 tegula for the calyptron of flies. The word is applied in other Orders 

 of Insects to quite other parts connected with the wing, and it would 

 be unfortunate if it should receive the application originally proposed 

 for it in Diptera by Baron Osteu Sacken. I do not, however, under- 

 stand the memoir of Osten Sacken referred to by Dr. Meade (Berl. 

 Ent. Zeitschr., 1896, p. 2S5) in quite the same way as our distinguished 

 British Dipterologist has done, for it appears to me clear that Osten 

 Sacken in it declines to justify the use of the terms tegula and 

 antitegula, and suggests that in place of them (see p. 288, I. c.) the 

 terms squama and antisquama should be used in a correct nomenclature. 

 In such case the calyptron would mean the squama when it acts as a 

 covering for the halter. This would be the more convenient nomen- 

 clature, because there are cases in which the squama does not act as a 

 calyptron. Thus we could describe the Tahanidce as possessing an 

 erect squama, but it would be scarcely connect to call it a calyptron. 

 Hence the reformed nomenclature proposed by Baron Osten Sacken 

 seems to mc to meet all the requirements of the case, and we can only 

 hope that he will himself consent to use it, instead of continuing the 

 incorrect application of the term tegula. 



Cambridge : February, 1897. 



"An Account of British Flies," vol. i, p. IS 



