172 



WILLIA OEXATA. 



also is slightly convex, the convexity being turned towards the circular 

 tube. The next cycle, the third, consists only of four tentacles, wliifh 

 all make their appearance on the other side of the main chymiferous 

 tube, just as far on the other side as the tentacles of the second 

 cycle were on this side of the main radiating tube ; the offsets of 

 the tube which reach these tentacles start slightly below the first, and 



are Ukewise bent towards the circular tube. I was not able to observe 

 the formation of the additional branches and tentacles. I refer this 

 species at present to the WilUa ornata of McCrady found at Charleston, 

 the specimens which I found (Fig. 276) not being advanced enough to 

 enable me to determine their difiercnce or identity. The tubes which 

 contain the clusters of lasso-cells (/, Fig. 279), running in the thickness 



.278. 



Fig. 279. 



of the spherosome from the circular tube to the height of the base of 

 the digestive cavity, were particularly well defined ; the longer tubes, 

 extending in the middle of the space between two chymiferous tubes, 

 contain three clusters of lasso-cells, made up of from four to five large 

 cells arranged in a chcle. Even at this early stage the ovaries were 

 well developed (Figs. 277, 278) ; they are elliptical bunches placed on 



Fig. 27C. Profile view of a young AVillia ; magnified. 



Fig. 277. I'art of the circular tube. ;, tubes running into the thickness of the siiherosomc, 

 containing large lasso-cells. 



Fig. 278. View of ovary of Fig. 27G. 



Fi;^. 279. The same as Fig. 278, seen from the abactinal pole. 



