l.">.l 



^fr. II. A. Bavlis on a 



WlutluM- It is continuous all the way ronnd, T am nnahlc to 

 stall". This (hu't, «Iiic'li a|)|)cars to be ciliated, j^ivos oil" 

 nuuuMons other very fine, ciliated duets, at \'\<^\\t ani;les to 

 itseit', uliii'h i)ass towards the periphery. In transverse 

 sections through the botiy-uall very delicate tubes, in whose 

 walls no cellular structure has been detected, can be seen 

 l)assing out between the buiulles of longitudinal and circular 

 muscles to the exterior. I have not succeeded in establishing 

 their connection definitely with tlie ciliated tubes above 

 mentioned, though it seems probable that such connection 

 exists. The ciliated tubes in the mesentery were visible in 

 whole preparations of nephridia, which weie removed 

 together with the mesentery, and mounted in glycerine. 

 Tiie distal ends of the tul)es, where they pass between the 

 muscles of the l)ody-wall, could, of course, only be seen by 

 the section method. 



These tubes in the body-wall are generally accompanied 

 by fine bl(;od-vessels, while the mesentery is also well supi)lie(l 

 Mith blood-vessels, sending branches to the nephridial lobes. 

 In the more anterior segments {i. e., in segments a shoit 

 distance behind the clitclluni) I have not succeeded in finding 

 any trace ol" ciliated ne|)hri(lial funnels, or any other kind of 

 internal nephiidial 0|;eniiig, in s[)ite of the examination 

 of several whole preparations and a considerable number of 

 sections. In the more posterior segments, however, i. e.. in 

 about the last third of the body, such funnels certainly 

 exist. In each segment in this region there is, near the 

 ventral nerve-cord, a single pair of nephridial lobes of a 

 much larger size than the I'cst, and each of these organs has 

 a duet which |)erfurates the septum in fiont and ends in a 

 well-developed funnel in the preceding segment. In other 

 respects, the arrangement of the ne[)hridia appears to be the 

 same as in the more anterior region. 



The external nephridial pores are exceedingly difficult to 

 detect, even in sections, being, appai-ently, the narrowest of 

 passages between the cells of tlie epidermis. In spite of 

 carelul (.'xamination under a comparatively high power, I have 

 been unable to recognize the pores in pieces of stripped-off 

 cuticle, even when taken from the posterior region, where 

 the internal funnels are undoubtedly present. There is a 

 series of minute lozenge-shaped "impressions" in the 

 cuticle, arranged iu a single row round each segment, in a 

 line with the little tubular invaginations surrouiuiing the 

 chtetai. These, however, are not pores, but are probably to be 

 cuinpared with the markings said to be the impressions of 



