360 MOORE. [Vol. XIII. 



filled with granules which impart to them a green-brown color. 

 The coelomic corpuscles have exactly similar characters, and 

 one finds frequent indications of their continuous development 

 by budding from the chlorogogen cells, just as Schaeppi (31) 

 has shown them to arise from other regions of the peritoneum 

 in the Polychaeta. By this means the chlorogogen cells give 

 up a part of their load of waste substances to the freely circu- 

 lating coelomic corpuscles, many of which are seen in various 

 stages of disintegration, thus finally freeing, partly in the solid 

 state, partly in solution in the coelomic fluid, the waste matters 

 which they hold. These products of disintegration are continu- 

 ously drawn into the nephridial current, passing into the 

 nephrostome, and from time to time expelled from the external 

 pore. Accumulations of disintegrated coelomic corpuscles are 

 abundantly found in all parts of the nephridial lumen, and 

 clouds of minute granules are often seen to be ejected from 

 the nephridio-pores. 



As the corpuscles are produced and broken down not only 

 in the nephridial somites, but also in the male, and to a less 

 extent in the female somites, which contain no nephridia, and 

 as the septa limiting these somites are nearly imperforate, the 

 suggestion arises that the genital ducts may to some extent 

 convey the coelomic fluid with its contained waste matter to 

 the exterior, and be in that sense excretory. The ciliary action 

 within the vasa differentia and the peristalsis of their walls 

 must necessarily force some of the fluid along with spermatozoa 

 to the sperm reservoir, and thence to the exterior; and, as the 

 ciliary action is constant and the duct of considerable capacity, 

 this stream may reach a not unimportant volume. With each 

 extruded ovum also a small quantity of fluid must be forced 

 through the ovipores, and if these remain open for any length 

 of time a considerable but intermittent current would be induced 

 by the pressure of the body-walls. It must be recalled, how- 

 ever, that chlorogogen activity is reduced to a minimum in the 

 ovarian somite. 



The following facts are significant in this connection. Among 

 the lower Oligochaeta the nephridia very generally lack blood 

 supply. Coelomic excretion is therefore predominant, and the 



