294 Mr. Ernest Ewart Unwin on the 
of the general Muscid character. Wesché* claims that 
the well-developed palps are not maxillary palps, as Lowne 
describes them, but labial palps, and that traces of the 
maxillary palps are often present in Diptera. He main- 
tains that in Muscidz, for instance, both labial and 
maxillary palps are represented (fig. 17 in Wesche’s 
paper). The structure of the proboscis of Drosophila 
Fie. 11. 
Head of fly (front view). ant., antenna; l.p., labial palps; mx.p., maxillary 
palps (abortive); oc., ocellus. (x 60.) 
bears out Wesché’s account. The chief part of the pro- 
boscis is formed from the labium, and well-developed 
labial palps are carried on its anterior surface. At the 
extremity is the labella, consisting of two symmetrical 
tracheated flaps. The flaps represent the paraglossz, 
and the chitinous transverse bands the ligule. Small 
abortive maxillary palps are clearly visible just below the 
attachment of the large labial palps (fig. 11). 
* Wesché (1904). 
