joSS?uneTffl ^^y^'^ Microscopcal Society. 339 
As this part of the skeleton projects considerably towards the front, 
the posterior two-thirds is cut off in the preparations commonly 
made for sale, as it offers an insuperable obstacle to the flattening 
process formerly in vogue. Connecting the fulcrum with the lower 
joint of the proboscis is the small irregular ring (h), for which I 
have at present no name. Attached to the exterior membrane on 
the front, are two chitinous processes, each bearing from six to 
eight long stiff hairs (&), and named the basal rings of the maxilljje. 
Near these will be found the two maxillary palpi (c and c') (brushes 
of Gleichen) ; respecting the function of these I possess no informa- 
tion, never having in the course of my observations noticed that 
the fly makes any use of them. Connecting the upper and lower 
joints are two long chitinous rods {I and Z'), having trumpet-shaped 
posterior extremities to which muscles are attached, and which play 
an important part in moving the lower joint. The skeleton of this 
joint consists of more pieces than that last described, and bears at 
its extremity the complicated lips. The most conspicuous piece is 
the mentum (^), which, hke most parts of the external skeleton, is 
covered with stiff hairs arising for circular pits, this terminates 
anteriorly in a forked process {n), described by Mr. Lowne as a 
spring closing the lips when at rest, the function of this portion is 
to support and control the motions of the back of the lips. On the 
opposite side, or front, is the Epiglottis {d), partially enclosed in 
folds of membrane (Plate XV., Figs. 1 and 3 d), upon disengaging 
this by means of a needle there are seen w^ithin the ligula (Figs. 1 
and 3/), described by some as a tongue or lancet ; and more in the 
interior the labium and labial palpi (Figs. 1, 2, 3 A and e), bearing 
at their extremity a forked pisce (Plate XV., g), supporting the 
upper surface of the lips. 
The hps I have endeavoured to represent in (Plate XIV.) the 
radiating tubes, which for want of a better name I must call 
Pseudo-tracheae, are the portion of their structure which usually 
attract attention at first sight ; and it is to their extreme beauty of 
arrangement and detail that the mounted shde owes its deserved 
popularity. The pseudo-tracheae above and below the oral aperture 
are arranged in four groups, each connected with a larger tube, 
these four main tubes emptying themselves into the oral aperture ; 
the ten central tubes on each side of the mouth open directly and 
independently, having disposed between them long forked append- 
ages ; the teeth (Plate XVI., Figs. 1 and 4), arranged in three 
rows, the back row of which perhaps are hardly to be considered as 
proper teeth, as they are attached rather closely to the membrane of 
the hps. The ofiice of these teeth is undoubtedly that of cutting 
instruments or scrapers. I have examined carraway comfits after flies 
have fed upon them and found them covered with parallel scratches, 
the distance of which, when measured with the micrometer, cor- 
