106 Larval mid Pupal HtaijcH of Scatopse Notata, L. 



the second to seventh segments. Each spiracle bears a number of 

 minute openings at its apex. 



There is also a pair of prothoracic spiracles, which are dorsal in 

 position. Each arises from an enlarged base and is a considerably 

 branched structure, with a length of about -24 mm. At the apex of each 

 of the branches are a number of minute openings. 



On the ventral surface of the thorax the sheaths of the legs, wings 

 and antennae are visible, ])ut they are much more closely attached to 

 the body than is the case with the pupa of Bibio((>). The head is ad- 

 pressed to the prothorax. and the antennal sheaths curve outwards and 

 backwards, extending to the base of the wing sheath of the same side. 



The leg sheaths lie side by side, those of the first and second pairs 

 meeting in the middle and, along with the wing sheaths, cover the 

 underside of the meso- and metathorax. The sheaths of the third pair 

 of legs are almost entirely covered by the wing sheaths, only their 

 extreme apices being exposed. The leg and wing sheaths extend nearly 

 to the posterior margin of the first abdominal segment (Plate X, fig. 3). 



The parts of the sheaths of the appendages which are directed out- 

 wards, are composed of a tough cuticle similar to that covering the 

 greater part of the body. Those portions of the sheaths which are closely 

 adpressed to the body, consist of a delicate colourless membrane. A 

 similar delicate membrane invests those portions of the body which lie 

 beneath the sheaths of the appendages. 



Dorsally the thorax bears a slight longitudinal ridge extending from 

 the hind margin of the mesothorax to the anterior extremity of the 

 pupa. This ridge is exposed by the slitting of the larval skin, and along 

 this ridge the pupal cuticle divides for the emergence of the imago. 



On all the abdominal segments, both dorsally and ventrally. are a 

 number of small oval depressions, which are slightly paler in colour 

 than the other parts. The pupa is covered with minute blunt processes, 

 which are usually circular in shape. These structures, howeA'^er, are 

 absent from the oval depressions just mentioned, from tiu^ inter- 

 segmental ])arts of the abdomen and from the spiracles niul tluMr bases. 



4. (;l-:XKH.\L IMvMAP>KS OX TFJK .M()i;i»H()L()(; V AND 

 AKFIXITIKS OF TWK LAKX'A. 



It has been already mentioned that both Dufoui' and Perris con- 

 sidered the Scatopse larvae, which they described, to be amphipneustic. 

 Bouche. on the other hand, stated that the larva carried nine pairs of 

 sj)iracles, which is the correct number. Dufour mentioned that the 



