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The larva (Plate LVII, tigs. 1, 2, 3 and 8) is a minute maggot- 

 like creature, bearing a strong superficial resemblance to a Dipterous 

 larva. It moves about actively in dust or sand,* and 

 is best recognized by shaking up the debris and 

 watching for moving particles, as it usually keeps below the superficial 

 layer. It consists altogether of fifteen segments, including the head and 

 the hidden terminal segment. Of these the posterior are the largest, the 

 posterior half of the body being distinctly thicker than the anterior, 

 though there is not quite that tapering appearance seen in the Muscid 

 larvae. The segments are rounded, and there are no pseudopodia or legs. 

 The head is small and conical, and bears a pair of simple cylindrical 

 and tapering antennae, at the apices of which there is a minute hair. 

 The base of the antenna is set on a small raised area at the side of 

 the head, dorsal to the mouth, and has around it a row of five or six 

 minute conical and apparently jointed processes. Each of the succeed- 

 ing segments down to the tenth bears a row of six minute hairs, inserted 

 in the middle of the length of the segment, and increasing progressively 

 though not markedly in length from before backwards, as the segments 

 themselves increase in size. The eleventh and twelfth segments bear 

 eight hairs each ; of these the twelfth is the largest of the body, and 

 bears the longest hairs. The thirteenth segment has six hairs, and is 

 considerably smaller than the preceding ones. The fourteenth segment 

 is still smaller, and has on each side a row of four hairs which are 

 rather stouter and longer than the rest, and are placed on the distal 

 margin of the segment. The fifteenth segment is very small, and 

 is concealed by the one in front of it. It bears terminally a row of 

 fifteen minute hairs on each side. Projecting from within the last 

 segment there is a pair of minute slightly curved and elongate pointed 

 processes, arising from a stouter base. 



The internal anatomy of the larva is simple, and strongly resembles 

 that of the adult to a much greater extent than is found in the 

 Diptera. The alimentary canal (Plate LVII, fig. 5) 



commences as a narrow oesophagus, which after a lntepn ^ anat my ' 

 . . larva 



short course joins a small conical proventnculus. 



The main portion consists of a sausage-shaped mid-gut, about seven 

 times as long as wide, which passes straight down the body without 

 convolutions. The four Malpighian tubes are inserted at its posterior 

 end ; these do not differ from those of the adult. The remainder 

 of the gut is coiled up in the last segments of the body. It consists 

 * It can also move actively on glass or smooth paper. 



