ON PERICHAETIDAE, 209 



and usually the number of them at the right side is not 

 the same as that at the left. The largest number, observed 

 in segment VI, was 29: at the right side 17, at the left 12; 

 it was in a worm from Sintang, with only a single pair 

 of papillae. In a couple of specimens I found only two 

 spermathecae in this segment, one on each side. In segment 

 VII the number of spermathecae usually is larger than in 

 the preceding; in one specimen T observed 30 of them, 

 15 at the right and 15 at the left side. The smallest 

 number I met with was 3 on each side. It is not always 

 in the largest specimens that the greatest number of sper- 

 mathecae is to be found. A specimen, 300 mm. long, 

 showed a single pair of them in segment VI, while in 

 segment VII there were 12, at the right side 7, at the 

 left 5; on the contrary one individual, 115 mm. in length, 

 had in segment VI five spermathecae, 3 at the right and 

 2 at the left, while the following segment showed 5 pairs 

 of them. 



Leydeu Museum, November 1898. 



ÏSTotes from tlie Leydeu Mixseum, Vol. XX.. 



14 



