too NOTES And meMoranAa. 



not unlike young examples of such a form as Coleocha'te scu- 

 tata without bristles (Phyllactidum, Kiitz.), as does possibly 

 the unnamed " nov. genus Ulvacearwn " described on jd. 76. 



Certain forms of Polyedrium, Sorastrum, Gongrosira, 

 Chlorotylium, and Ulothrix are described, as well as 

 Microthamnion, GEdogonium, and Bulbochsete. 



An Q\^?i\\?LmediSpirogyraannularis\s described, which seems 

 remarkable. In it the filament tapers towards the (upper) 

 extremity. The cells of the cylindrical (lower) j^ortion are 

 very short, being, in fact, nearly one half broader than long, 

 the cell-wall rather thick ; the endochrome forms a complete 

 ring, slightly twisted. To judge from the figure, the endo- 

 chrome of the upper or tapering cells is different, and forms a 

 longitudinal axile band. Quere, is this truly a Spirogyra?J 



A puzzling little, very slender, filamentous form is described 

 and figured, but not named, believed by the author to come 

 imder Cymatonema (by an error printed " Cymatopleura"), 

 but having, he thinks, also possibly as much right to be 

 placed to Zygnemese. The cells are elongate, comjjaratively 

 rather thick-walled, more or less regularly hexagonal, colour 

 bright green. 



ActidesmumHookeri (n. s., Reinsch) is a curious little alga, 

 somewhat calling to mind Sciadium arbuscula (Al. Br.). The 

 thallus is formed of families of a few spherical cells, each 

 single cell at the summit of a short slender hyaline pedicel, 

 several of which radiate in a whorl from the summits of a 

 number of longer and thicker hyaline pedicels, which latter 

 themselves radiate from a common centre ; propagation by 

 zoogonidia. It thus seems to differ, so far as can be judged, 

 from Sciadium by the aggregate family not standing on a 

 substratum by a common pedicel, and by the ultimate cells 

 being comparatively large and spherical, not elongate. 



Ccelastrum {^phcerastrum) verrucosum (n. s., Reinsch) is a 

 well-marked form, characterised by the external subacute 

 verrucse. 



Characium Dyerii (n. s., Reinsch) has a singular habitat 

 — on the backs of entomostraca — cells elliptico-oval, contents 

 granular, amylaceous, colour pale green. 



Of Desmidiese several new and well-marked species are 

 described, a few of which, however, are not named. Cos^ 

 marium pseudomargaritiferum (Reinsch) appears to be the 

 same as C. Portianum (Archer). It has a very singular 

 zygospore, globose, thick- walled, and covered by pits, that 

 is, scrobiculate ; hence de Bary's figure (' Untersuchungen 

 ueber die Familie der Conjugaten,' t. , f . ) cannot refer 

 to this species; in fact, to that extent the zygospore of the 



