67 



The colour of the worm is greenish yellow, except on the clitellum, 

 which is whitish and very noticeable. Through the transparent body- 

 wall the prostata-glands and ventral nerve-cord are visible. 



The prostomium is inverted and could not be recognized. 



The male generative pore is situated upon a papilla; a depressed 

 median ventral area exists upon segment XVII, XVIII and XIX, 

 bounded laterally by a glandular ridge, in the middle of which the 

 papilla of the male pore is situated. À single female pore on an ob- 

 vious glandular area. A pair of papillae upon the anterior margin of 

 segment VII, on a short distance from the ventral median line. 



About 44 setae, arranged in a continuous row, in the segments 

 in front of and behind the clitellum; this number increazes forwards, 

 so that upon segment VII 60 bristles are to be found. In the anterior 

 segments however it decreazes gradually; on the clitellum no setae 

 were observed, except upon segment XVI, where there occur five on 

 each side of the ventral median line. 



The intestinal canal resembles that of other Perichaetae ; the 

 pharynx is covered with glands and a narrow oesophagus occupies 

 segment VI and VII , widening out in segment VIII , where it passes 

 into the gizzard , situated in segment IX and X. The intestinal coeca 

 are short and obtuse. 



There is one pair of spermathecae in segment VII; they con- 

 sist (PI. Ill, fig. 27) of a long and tubular pouch , somewhat dilated at 

 its internal extremity, and a slender diverticulum, that measures about 

 twothirds of the length of the main pouch , and consists of a small sac 

 with a long and narrow excretory duct. The pores of both spermathecae 

 are probably situated upon the papillae of segment VII. The prostata 

 is a well-developed gland, opening externally by a S-like bended duct, 

 without muscular bulbus. The nephridia are diffuse. 



As far as I know of, this is the smallest Perichaeta-s^ecies hitherto 

 described; the examples however appear to be in a state of sexual 

 maturity. 



Three Perichaeta-species , possessing only a single pair of sperma- 

 thecae , are already described from the Malayan region, viz. P. quadra- 

 genaria Perr. 1 ), P. sangirensis Mich. 2 ) and P. racemosa Rosa 3 ). The 



1) Nouv. Arch. T. VIII, p. 122, PI. IV, fig. 69. 



2) Jahrb. Hamb. Wissensch. Anstalten, T. VIII, 1891, p. 36. 



3) Ann, K. K. Naturli. Hofmuseuius, T. VI, 1891, p. 399, PI. XIV, fig. 8. 



