14 ON A REMARKABLE SVLL1S-BUD. 



bladder-shaped bodies , capable of being extruded , which 

 he believes to be respiratory organs *). 



The eyes (fig. 9) of our worm , though not so highly 

 developed as those of the Alciopidae , however seem to 

 have a more differentiated structure as the large eyes of 

 Genetyllis oculata described by Mac Intosh 2 ). There is no 

 lens , but the total eye-cavity is occupied by a vitreous 

 body , composed of exquisitely delicate fibrils , which era- 

 diate from the fundus of the eye to the corneal surface. 

 Immediately within the vitreous, and not always distinctly 

 separated from it , is a layer of short fibres , thicker as 

 those of the vitreous and darker stained , which undoub- 

 tedly corresponds to the rod-layer of the retina in the eye 

 of the Alciopidae. Outside of the rod-layer we have a 

 layer of orange-coloured pigment, resting on the outer 

 layer of the retina, which contains numerous nuclei, while 

 the cells are not well-defined. 



Concerning the systematical position of these Syllis-sipe- 

 cimens , there can be no doubt that they are originated 

 by budding; this may be concluded from the presence of 

 bristles in the first segment of the body , from the total 

 absence of tentacular processes on the head , from the struc- 

 ture of the alimentary tract, having no proper pharynx 

 and proventriculus. This may also be presumed from the 

 extraordinary development of the segmental organs, for 

 we know from Ehlers' researches , that in the posterior 

 segments of the body of the Syllidae , which contain the 

 generative products , the segmental organs become much 

 enlarged 3 ). 



Albert mentions also about the segmental organs of the 

 swimming bud of Haplosyllis spongicola Gr. , that their 

 middle region acquires a glandular appearance and much 



1) Die Borstenwiirmer, p. 659 and 676. 



2) Challenger Keport, Zoology, Vol. XII, p. 170, pi. XXXIII, A, figs. 1—8. 



3) loc. cit. p. 231. 



.Notes from tht- Ijeyden Museum, Vul. XI. 



