Myriopnda of Dominica. All 



Strongylosoma semirugosum, sp. n. 



? Syu. Strongylosoma spilonotumy Gerv. lus. Apt. iv. p. 117. 



Colour ochraceous above, with a faintly marked median, 

 dorsal, paler band, testaceous beneath ; legs and antennae 

 testaceous. 



Tergites shining, the anterior half of each less so than 

 the posterior, the latter feebly rugose ; those of the pos- 

 terior region of the body more rugose than those of the ante- 

 rior ; the posterior portion of each, with the exception of the 

 first four and the last three, marked with a transverse groove, 

 which extends almost from keel to keel ; keel of the second 

 somite appearing as a longitudinal ridge, keels of the third 

 and fourth somewhat rounded and very small, those of the 

 succeeding somites more rounded and larger ; those keels that 

 do not bear stigmata less conspicuous than those that are 

 provided with them ; first tergite without trace of keels, with 

 rounded lateral margin ; the lateral and antero-lateral margin 

 with raised edge. 



Head-plate marked above with a conspicuous median lon- 

 gitudinal groove, which extends from the area between the 

 antennal sockets beneath the first tergite ; lateral border of 

 head-plate with raised margin ; anterior margin beset with 

 hairs, medianly excavated and laterally rounded. Distal four 

 antennal segments thickly hirsute, the proximal three 

 sparsely so. 



Aiial tergite produced behind into a rounded setiferous 

 prominence, which considerably overlaps the anal valves, 

 furnished with a transverse row of setai : anal valves (pleurites) 

 with elevated free margins ; anal sternite evenly roanded. 



Legs hirsute, the proximal segments less so than the distal ; 

 distal two segments in the male furnished beneath with a 

 tuft of hairs. 



Basal (internal) segment of copulatory foot of the male 

 irregularly cylindrical ; second segment small, projecting pos- 

 teriorly, somewhat elliptical, with its long axis at right angles 

 to that of the basal segment, densely hirsute ; from its ante- 

 rior surface springs a slightly twisted elongate lamina, dis- 

 tally bifid, and curled upon itself so that the bifid extremity 

 is almost in contact with the proximal end of the segment. 



Total length 28 millim., width 2^ millim. 



Five male specimens. 



Tiie descriptions of the American (and other) species of 

 Strongylosoma are, with one or two exceptions, so brief that 



