248 Chas. W. and G. T. Hargitt. 



nessed the entire operation. As compared with AureUa the 

 polyps of Cyanea are relatively small; they are whitish in color, 

 making a most beautiful sight when viewed together in a watch 

 glass by reflected light against a black background, (cf. text fig. 1,). 



Stolonization. — This is much less common than in Aurelia, 

 though not rare. In fig. 42 is shown such a case. Stolons may 

 arise from the body or base of the polyp as shown in the figure, 

 and may be very delicate thread-like structures, or often some- 

 what massive, and these may sub-branch, thus giving rise to 

 little colonies of polyps formed by this mode. The budding of 

 polyps directly from the body of a parent was not observed in 

 Cyanea, but is not uncommon in Aurelia. 



Strobilation.- — This feature is rather inconspicuous in Cyanea, 

 owing to the relatively small size of the polyp, and the strobilse 

 are relatively few in number, often but a single one arising from 

 a given polyp at a given time. In other cases the polyp becomes 

 polystrobilous, from three to five ephyrse being set free in early 

 succession. In figs. 44-46 are shown phases of strobilation as 

 drawn from nature by Mr. H. B. Bigelow, for which kindness it 

 is a pleasure to express thanks. 



It remains to mention another feature, namely, that concerning 

 the origin and development of the tentacles. These arise by a 

 process of budding from the margin of the peristome, and are 

 usually four in number, constituting the primary set. In many 

 cases, however, only two tentacles appeared at first and on oppo- 

 site sides of the mouth; later two others would arise in the appro- 

 priate intermediate positions. In a few cases the polyp seemed 

 organized in a trimerous fashion, three primary tentacles arising 

 about a triangular mouth, to be followed later by a second set 

 of three tentacles at intermediate positions, rendering the speci- 

 men hexamerous. The average number of tentacles in the polyp 

 of Cyanea is sixteen, though this number is not definite, as many 

 were to be found having twenty or more. In a few instances 

 bifurcated tentacles were found, a not unusual condition among 

 coelenterates. 



