112 



ISEN 



son, the well-known zoologist, to whom I am indebted for several 

 interesting Oligochaeta. 



Characteristics. This species is characterized by its spermathecae 

 without diverticles and by the position of its chylus cells in somites X, 

 XI and XII. In most other species the chylus cells are found in 

 somites posterior to clitellum. 



FIG. 72. Fridericiajohnsom. 



Chylus cells. The unusual position of these cells has just been 

 mentioned. The cells are long and narrow, with somewhat warty 

 surface. The nucleus is oval, situated below the center of the cell. 

 The chylus cells are separated by rows of single epithelial cells. The 

 latter with round nuclei. 



FRIDERICIA FUCHSI sp. nov. 

 pi. xvu, figs. 1-3 ; text-figs. 73 and 74. 



Definition. Length 18 mm., width .5 mm. Somites about 65. 

 Setae slightly curved, more so in the anterior somites than in the pos- 

 terior ones, in fascicles of four and five, the inner setae being much 

 shorter. Dorsal pores commence with VII. Head-pore between 

 prostomium and somite I. Prostomium prominent. Sexual papillse 

 small. Septal glands large, IV to VI. Peptonephridia with from 

 four to six branches projecting from a common base. Brain almost 

 circular, convex posteriorly and anteriorly. Dorsal vessel rises pos- 

 terior to clitellum. Intestine with a thin layer of chloragogen cells. 

 Chylus cells in XIV to XVI, long and narrow, separated by very 



