346 ALFRED GIBBS BOURNE. 



maintains that this species is not identical with S. appendi- 

 culata, as Vejdovsky believes it to be. As Stolc^ has pointed 

 out, this is very probable, and the difference is to be found in 

 the arrangement of the tactile papillae ; but I agree with Stole, 

 that Bousfield has fallen into a great error in associating 

 Ophidonais serpentina with the genus Slavina. The 

 absence of capillary setae distinctly marks Ophidonais as a 

 separate genus. 



Stylaria, Lamarck (see woodcut). 



Four cephalized segments in addition to the peristomiai 

 segment are present in the bud, and remain well marked in 

 the fully grown head. 



The prostomial tentacle is very long. 



The dorsal setse are capillary. 



There are no branchial processes. 



Eyes are present in the only known species. 



1. S. lacustris. 



A full synonymy of this species, which is perhaps most 

 widely known asNais proboscidea, is given by Vejdovsky. 



I have occasionally observed specimens in which dorsal 

 setse were present in the one or two most posteriorly placed of 

 the usually cephalized segments. I can only suggest that these 

 were abnormal individuals, but it is a matter worthy of further 

 investigation. I described the process of budding in this 

 worm at the meeting of the British Association at Aberdeen, 

 in 1885. I quote here the substance of the note published in 

 the report of that meeting. I have altered the numbering of 

 the segments to make it accord with the system adopted in the 

 present memoir, in which the peristomiai segment is called 

 segment i. 



" When budding is about to commence, a slight thickening 

 of one of the septa which separate one coelomic segment from 

 another occurs. This thickening increases, the body-wall in 

 the region thickens, and an actual bud is here formed. This 



1 * Zoologisclier Anzeiger,' vol. ix, 1886, p. 502. 



