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General History of the Marine Polyzoa. 197 



men which I have examined, and is, I think, the minutest 

 which I have seen. 



Several stemmed Cheilostomatous forms, some of which 

 are extremely curious, have been brought to light in com- 

 paratively recent times ; they are Kinetoskias, Kor. & Dan., 



also a Bicellarian group with four species, and Rhabdo- 



zoum, mihi, which is referable to the Eucratean family, in 

 addition to the present genus. In most of these forms the 

 stem probably represents a modification and adaptation of 

 the structure known as the " radical fibre ;" in the present 

 case, as I have already stated, it is composed of aborted cells. 





Stolonella, no v. gen. 



Gen. char. — Zoarium consisting of a creeping stolon, 

 and zooecia distributed upon it. Stolon chitinous, free in 

 itself, but attached at intervals by adhesive branching disks, 

 which originate from short stolonic offsets, jointed, more 

 or less branched. Zooecia erect, scattered, always deve- 

 loped close to a joint, attached to the stolon by the pointed 

 lower extremity of the dorsal surface, subcalcareous, boat- 

 shaped, aperture occupying the whole front, closed in by 

 flattened spinous ribs, united together ; orifice terminal. 



The true stoloniferous character of this form seems to call 

 for its separation from Beania, as represented by our British 

 B. mirabilis. The cells in the latter species are borne at the 

 extremity of a slender pedicel, which takes its origin on the 

 dorsal surface of a neighbouring cell ; and it is in this way only 

 that the members of a colony are united. There is no common 

 stolon to which the individual zooecia are jointed. Each cell 

 is attached by means of a radical tube emitted from its dorsal 

 surface, which spreads itself out into a fibrillated disk and 

 holds it to its place. But in Stolonella the plan of structure 

 is quite different and much less simple. The zooecia are borne 

 on a distinct stolon, as in Eucratea or Valkeria, and are 

 attached by the extremity of the dorsal surface to a slight pro- 

 minence on the creeping stem. The stolon is not adhesive, 

 as in the genera just mentioned, but is fixed by a special ap- 

 paratus of disks developed at intervals along its course. It is 

 regularly jointed, and close to the joint a branch is given off 

 at right angles on each side. These branches are occasionally 

 both of them very short, bearing at the extremity an adhesive 

 disk ; more commonly one only is arrested in development 

 and carries a disk, the opposite one lengthening out into a 

 jointed stolon, like that from which it originates, and bearing 

 a line of cells. This structure is evidently a derivative from 



