254 



Messrs. C. Reid and J. Groves. 



ampliati, septis crassis in cellulas distinctas eo breviores quo latiores divisi, 

 sex sensim angustati, extrinsecus propulsi, ideoque in sulcis inter tubos 

 majores positi, omnes rosellas more internodiorum ferentes, majores praeterea 

 ramulos singulos verticillatirn dispositos emittentes. Hamuli e cellula una 

 tubulari et nonnullis abrupto expansis nodiformibus vertieilla singula sex 

 rosellarum more tuborum corticalium emittentibus constantes. Fructus 

 solitarii, bini vel terni, uno latere (verisimiliter superiore) ramuli e rosellaa 

 centro (?) orti, oogonia singula quasi braeteata referentes. Oogonium com- 

 positum ex ovo et ex cellulis 5 elongatis spiraliter tortis, iis Characearum 

 recentium similibus, sed utriculo circumdatum e cellulis bracteiformibus 

 elongatis adnatis effecto vel iis incluso. Antheridia ignota. 



The principal characteristics of the genus appear to be — 



1. The remarkable club-like nodes of the stem, from which we derive the 

 name. 



2. The production on the stem and branchlets of clusters of small clavate 

 processes. 



3. The presence of a utricle enclosing the oogonium. 



The club-like nodes of the stem are of two kinds. The first, which we 

 have styled " spindles " (Plate 8, fig. 13), taper at each end into the normal 

 stem. Although we have not found two of the spindles connected, we 

 conclude, from the fact that they are the more numerous, that each stem 

 produced two or more of them. The second kind, which we have styled 

 " heads " (fig. 5), are terminal and are turbinate, tapering below, and more or 

 less flattened above. The normal stem forming the internodes is composed 

 of a single thick-walled tube, surrounded by twelve equal contiguous sheathing 

 tubes, or series of cells (figs. 9 and 10), resembling the so-called " cortex " of 

 existing Chareae, except that the number is apparently constant. At the 

 ends of the spindles and at the base of the heads a marked change takes 

 place in the sheathing tubes, six alternate tubes rapidly enlarging and 

 becoming broken up by well-marked transverse septa into separate cells, 

 which diminish in length as they increase in diameter, the other six tubes 

 gradually diminishing in diameter and being forced outwards, so that instead 

 of, as in the internodes, lying side by side with the alternate tubes, they 

 occupy the furrows between their outer curves (figs. 11 and 12). 



The clusters of small clavate processes, which we have styled " rosettes," 

 are produced at more or less regular intervals on the sheathing tubes of the 

 stem, both on the nodes and internodes ; they are symmetrical, the processes 

 diverging in all directions, rosette fashion, the outer being adnate to the 

 sheathing tube from which they originate. With the interior of the tube 



