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ME. J. G. H. FREW : MORPEOLOGY OF THE HEAD CAPSULE 
his nomenclature in this niiitter. On each side the parocciput bears an 
articular surface of somewhat complicated nature [art.) with which the 
anterior end of the chief neck sclerite on each side articulates. 
The ventral half of the riiii of the occipital foramen is thickened (pa.p.), 
and the posterior arms of the tentorium appear to arise from this thickened 
rim. This is the Parapostgenal thickening (Peterson, p. 24). 
Two long chitinized ridges (r.) occur on the inner surface of the occiput, 
one on each side, arising from the dorso-lateral region of the parocciput and 
extending dorso-laterally towards the eyes. A median thickening, which is 
present in many Cyclorrhapha in addition to the above, is not found in 
Chlorops. 
Fig, 5. 
Lateral view of the proboscis. 
The Antennce consist of three basal joints and an arista arising from the 
third joint and itself three-jointed. The second joint of the antenna has a 
cone-shaped apex which fits into the base of the third joint. The basal joint 
is a ring-shaped sclerite and is imited to the second joint by a membranous 
region of considerable extent. There is a relatively large pit on the under 
surface of the third joint which is probably a sense-organ, but which has not 
yet been closely examined. The arista is minutely pilose. 
Mandibles are absent. 
The Labium iorms the greater part of the proboscis. The following is a 
brief rhume of Peterson's views on the homology of the Dipterous pro- 
boscis : — The membranous basiproboscis is made up of submentum, mentum, 
