with descriptions of two neio species from Formosa. 361 



Abdomen of the $. (Fig. 1 dorsal, Fig. 2 ventral view.) — The 

 abdomen of tlie specimen from Formosa disagrees in some small 

 details with Speiser's description. Tergites 2, 3 and 4 have short 

 bristles on their surface, in addition to the long bristles on their hind 

 margins. The anal segment has scanty bristles on its surface, as 

 well as at its hind corners. Of the sternites, only the basal one has 

 fine bristles on its surface. Sternites 2, 3 and 4 are quite bald, 

 except for the fine bristles along their hind margins. As in the $ , 

 the basal sternite bears some long bristles rather far apart, just in 

 front of the ctenidium. 



Abdomen of the 5 . (Fig. 3 dorsal, Fig. 4 ventral view.) — The 

 distinguishing characters of the 9 , now described for the first time, 

 lie in the form of the abdomen. 



Basdl tergite firmly chitinised, with conspicuously rounded hind 

 margin ; quite bald, except for 2 groups of 4-6 strong, moderately 

 long bristles on the hind margin, one group immediately on either 

 side of the middle line. Tergite 2 rather long, firmly chitinised, with 

 hind border much less curved ; the surface quite bald, hind margin 

 set with strong bristles of varying length, at the sides moderately 

 long, in the middle very long but not very close. Tergite 3 consist- 

 ing anteriorly of soft whitish, extensible skin, quite bald; posteriorly 

 of a yellowish chitinised portion more than four times as broad as 

 long (Fig. 3a), its surface bald or with few short bristles, its hind 

 margin bearing strong bristles of varying and alternating lengths, 

 some very long. Anal segment firmly chitinised (except right at the 

 base), truncated-conical, its length about equal to its breadth at the 

 base, breadth at apex less than i that at base ; base bald, followed by 

 area bearing strong outstanding moderately long bristles rather far 

 apart ; posterior part of segment quite bald ; hind margin bearing 

 several rather short bristles, with a long bristle at either angle. 



Basal sternite large, with scanty short fine bristles on the surface 

 except in the median-basal part, and with a row of long bristles a 

 little before the hind margin ; ctenidium not strongly developed, 

 teeth in the middle rather far apart. Next follows a large area of 

 soft whitish extensible skin, with numerous rather short strong 

 bristles, and 8 long ones arranged in a curved transverse row (Fig. 4a). 

 Beyond this area are two oval, rather convex, chitinous plates 

 (Fig. 4?>), nearly touching at the middle line ; their basal portions 

 bald, posterior portions with a few short strong bristles, hind margins 

 with anumber of moderately and very longstrongbristles. Immediately 

 behind these plates is a short chitinous segment (Fig. 4c), extending 

 across the body, its hind margin bearing short bristles medially, very 

 long strong bristles on either side. Behind this, just in front of the 

 genital opening, is a chitinous plate (Fig. .5), as long as or longer 



