THE GENERA AND yPEClES OF SYMFHYLA. 39 



this augle is slightly louger than the other seta3^ and con- 

 siderably or much shorter than the breadth of the proximal 

 anteunal joints. The cential rod is scarcely visible in more 

 than half of the normal length, without frontal branches, and 

 terminating behind rather far from the posterior margin, 

 without visible oblique posterior rods or posterior area. 



Antenna3. — The number of joints varies essentially, ac- 

 cording to the lengLli of the specimens, from twenty-two to 

 forty-one. The seta3 on the inner side of the proximal joints 

 are as long as or slightly longer than those on the exterior side 

 (fig. 1 h). The second whorl begins below near the end of 

 the basal third of the antenna); a little more distant from 

 the base it has a seta on the upper side, but the whorl is 

 only completely developed cm the outer side in the most 

 distal joints in large specimens. About the middle of the 

 antennae (6g. 1 c) a third whorl begins on the lower side, but 

 it contains only one seta, and towards (he end of the 

 antenuee two or three setie. The seta) in the central whorl 

 are long on the upper and only a little or scarcely shorter on 

 the lower side. The terminal joint has a large, long-stalked, 

 striped organ on a conspicuous protuberance, two small, very 

 short-stalked striped organs, besides a subglobular organ 

 without stalk and stripes and some styliform, small sensory 

 seta3. 



Scuta. — The second scutum (fig. 1 d) has its posterior 

 margin straight or slightly convex in the middle half; its 

 autero-lateral settc are directed somewhat forwards, long, 

 somewhat longer than or nearly twice as long as the breadth 

 of the basal antennal joints ; of its lateral seta3 two pairs are 

 longer than the other, and the postero-lateral pair, being the 

 longest, is only half as long as the antero-lateral pair, and 

 directed essentially backwards. The first, third, fifth, sixth, 

 and eighth scuta each with an antero-lateral seta about 

 as long as that on the second scutum (in one specimen 

 these seta) on the sixth and eighth scuta were considerably 

 shorter than the anterior ones), and one pair or two pairs of 

 lateral sette developed as on the second scutum ; the fourth, 



