104 SMYNTHUEUS. 



same direction, thoiigli witli tliree gentle curves 

 resembling in outline, though less abrupt than, 

 those of a bow or a reversed S"r The front line of the 

 mandible, on the contrary, makes a sudden change of 

 direction at the beginning of the molar portion, so that 

 the terminal part of the mandible seems to lie in a 

 different plane from that of its basal part. The 

 maxillae are a little shorter than the mandibles. The 

 width varies, being smallest towards the upper end 

 and greatest towards the middle. The upper extremity- 

 is terminated by a somewhat complicated system of teeth. 

 First, there are three strong curved teeth, the outer one 

 being like the largest, and the inner one the smallest. 

 In addition to these are two lamellae, whose inner edges 

 are beset with a row of minute sharp projections. 

 Lastly, there is a large central, somewhat fan-shaped 

 lobe, the central part of which bears some fine hairs on 

 the margin. All these parts ajopear to have some 

 power of independent movement. The body of the 

 maxilla is strengthened by a chitinous framework; 

 down each side runs a strong rib, while the two are 

 connected at the centre by a transverse piece, which 

 is also continued on the inner side a little way beyond 

 the rib, and curves at the same time so as partly to 

 surround the softer parts. 



The two lateral ribs converge to meet one another 

 at the base as at the apex. At the former, however, 

 they enclose a space which has the form of an acute 

 triangle, while at the basal end they curve round to 

 meet one another. At the base the chitine is rounded 

 off on the outer side, but is produced into a sharp 

 point on the inner edge. The palpi are short, 1- 

 jointed, rounded but not tapering at the free end, and 

 with two longish set^e and one or two minute hairs, 

 none of them, however, attached at the apex. The 

 second pair of maxillae are membranous and delicate. 

 Their form is somewhat difficult to describe. At the 

 extremity are two teeth of unequal size ; on the basal 

 side of these are three more or less projecting lobes ; 



