THE GENERA AND SPECIES OF SYMPHYLA. 29 



or feebly angular behind tlic mandible. The seta inserted in 

 front of the posterior end of the mandible is longer than the 

 breadth of the basal antenual joint. The central rod is 

 conspicuous in its whole length, with moderately robust 

 frontal branches, posteriorly connected with a triangular area, 

 without distinct oblique rods, at the hind margin of the head. 



AntenuEe. — According to my own experience the joints 

 vary from nineteen to fifty ; Latzel states the variation to be 

 even from eighteen to fifty-five. The second whorl begins 

 on the lower side before or at the end of the first third of the 

 antennse, and shortly afterwards on the upper side (fig. 1 /) ; 

 on the distal half, or at least the distal third of the antennae 

 the secondary whorl is complete on the outer side, and at 

 least one seta of a third whorl is found on the lower side ; 

 the setae in the whorls are rather long. The terminal joint 

 with a rather long striped organ, one or two small organs of 

 the same quality, and some shorter fine hairs among the 

 common setfE. 



Scuta. — The second scutum (fig. 1 Jc) posteriorly rather 

 deeply emarginate ; the bottom of the emargination not 

 angular but curved, and the broad posterior lobes rounded 

 without vestige of any angle; an antero-lateral seta can 

 often be pointed out, but is always much shorter than the 

 breadth of the proximal antennal joint and directed essen- 

 tially backwards ; the other marginal setfB vary frotn rather 

 to very short. The thirteenth scutum is sometimes shaped 

 nearly as the second, but often (fig. 1 I) it has a more or less 

 deep incision into each posterior lobe ; in this case the shape 

 of the twelfth and eleventh scuta presents transition forms 

 between the penultimate scutum and the anterior scuta 

 shaped as the second one. The last scutum (fig. 1 /) pos- 

 teriorly with the characteristic median cavity described above 

 on p. 13. 



Legs. — The last pair (fig. 1 m) has the tarsus somewhat 

 widened, three and a half to four times longer than deep; 

 the setse along the dorsal margin of the tibia, metatarsus, 

 and tarsus are short, five to six in the outer row on the 



