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H. M. Morris 
and having the form shown in Plate III, fig. 6. At its distal extremity each 
process bears several projecting spines. These processes bear some resemblance 
to those described by Keilin(3) as Baguettes orales ’ (oral rods) in carniv orous 
Anthomyid larvae. 
Tracheal System. The tracheal system is amphipneustic, a pair of spiracles 
being situated on both the first and last segments of the body. 
Both pairs of spiracles are very alike in size and structure and are brown, 
chitinised outgrowths from the body-wall: each spiracle communicates with 
the exterior by means of four oval apertures situated at its apex (Text-figs. 3 
and 4). 
2. THE PUPARIUM. 
The puparium is brown, with the segments fairly clearly marked. It is 
about 5-0 mm. in length. 
Dorsally there are several conspicuous constrictions. The prothoracic 
spiracular horns of the pupa emerge from the puparium through a pair of 
holes situated in a somewhat lateral position on its dorsal side, at the posterior 
end of the fourth body segment of the larva (Plate III, fig. 2). 
These horns are about 0*23 mm. in length, and their distal half bears two 
rows of minute openings, about sixteen openings in each row. Both pairs of 
larval spiracles remain as conspicuous dark projections from the puparium, 
and the mandibular sclerite also projects at the anterior extremity. 
3. THE PUPA. 
The pupa, seen on removal from the puparium is white, with the ap¬ 
pendages of the adult fly closely adpressed to the body. Its general characters 
can be seen on referring to Plate III, fig. 3, and scarcely need detailed 
description. 
The head is of moderate size, and the antennae are large and are produced 
in a long slender process. The palpi are conspicuous and conical in shape. 
The labrum is short and flattened. The legs lie side by side, the tarsi of the 
posterior pair projecting slightly beyond the apex of the abdomen. 
4. EMERGENCE OF ADULT FROM PUPARIUM. 
When the adult fly emerges from the puparium, the latter is split in the 
following way. A circular cap, consisting of the skin of the cephalic region 
and thoracic segments of the larva, is split off by means of a fissure passing 
round the body between the third thoracic and first abdominal segments. 
A quadrangular plate is split off in addition, and it consists of the whole skin 
of the dorsal surface of the first three abdominal segments. 
This plate may become completely detached, or may remain slightly ad¬ 
hering at its posterior end to the anterior margin of the fourth abdominal 
segment. 
