BY VERA A. IRWIN-SMITH. 



801 



to one-fiftli the total length of the body 

 0"04o iiini. ill front of the 

 anus, and extend forward 

 for a distance, which 

 varies from 0-092 toO-188 

 mm., according to the age 

 of the animal, and the 

 number of seta". The 

 outer rows (Figs. 49, 50, 

 6».r.)are laterally situated, 

 separated by a wide in- 

 terval from the inner 

 rows (i-r.), which are in- 

 serted very close together, 

 and in pairs anteriorly. 

 Further back, they alter- 

 nate irregularly, and the 

 two rows are not so clear- 

 ly distinguishable. They 

 usually begin further for- 

 ward, and their sette are 

 much shorter than those 

 of the outer rows. 



In the male, the outer 

 rows are composed of 

 compound and simple 

 setiw alternating irregu- 

 larly, the simple setie 

 (Fig. 49, fi.s.), being fewer 

 in number, and shorter 

 tlian the compound (c.s.), 

 and very slender. Four 



The rows be'nii about 



Figs. 49, 49( 



or five, short, simple set«e continue the outer rows back on either 



'•'Posterior region of trunk. The tail-gland and penial setie are seen 

 in outline through the body-wall; ( x 386). 



Fig. 49a. — Compound seti^ of ventral row; ( x 630). 



