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groove (fig. 10). The lateral and the dorsal margin form a thin and 

 narrow rim, which is smooth edged, exhibiting neither serration nor 

 cirri. The mouth opens on a gentle elevation on the ventral side near 

 the anterior end of the segment. No bristles are present. 



The thoracic segments, 7 in number, are about 3 m . m. broad. The 

 anterior end of each surrounds the posterior end of the next preceding 

 segment somewhat in the manner of a collar. The setae are placed at 

 about the end of the anterior third of each segment. 



The abdominal segments, of which there are 12, are marked off from 

 one another by simple grooves. The first 3 abdominal segments (3.5 m . m. 

 across) are of about the same size and shape, being broader than long 

 like the thoracic segments. From the fourth abdominal segment 

 backwards, the segments grow successively longer at the expense of 

 breadth, until the last abdominal segment is about twice as long as, but 

 considerably narrower than the first abdominal segment. The groups 

 of setaa in the first 2 abdominal segments occupy much the same position 

 as in the thoracic segments. In the third abdominal segment they are 

 situated at about the middle, while in all the following abdominal 

 segments they lie approximately two-thirds the length of the segment 

 away from the anterior end. 



The tail consists of the three last segments. Thesj are of nearly 

 the same dimensions as the last abdominal segment but are destitute 

 of bristles. The very last or the anal segment has the posterior border 

 developed into a rim with finely and uniformly serrated edge. This 

 rim surrounds a flatly conical elevation, the summit of which is 

 occupied by the anus (fig.9). 



The setae on the first setigerous (i. e., the first thoracic) segment 

 are all acicular, comprising two kinds differing in thickness ; but neither 

 of these are capillary. Uncini are wanting. 



In all the remaining setigerous segments, there are on either side 

 a dorsal flattened tuft of capillary seta? and a ventral row of uncini. The 

 capillary ^eta? are of two kinds (fig. 12, a and Ò) ; both are long, slender 



