and on a new SiJecies 0/ Protococcus. 427 



does it not in tlie apr^s-moi-le-deluge system of those reckless 

 soi-disant " naturalists " whose chief object is to see their 

 names dangling after a description oftentimes incomplete and 

 sometimes even culpably imperfect ? 



I do not mean this to apply to the present instance ; but 

 when one reads in Mr. Archer's faithful description of Soras- 

 trum sjmiulosum (Proceed. Dublin Microscop. Club, 21st Sept. 

 1865, p. 40), that, although each individual of the group of 

 Sorastrum possesses four spines, when one individual '' pre- 

 sents its broad or cuneate side to the observer, it often 

 happens that only two spines seem to exist, as one is behind 

 and hidden by its companion" (a condition which I myself 

 have often witnessed) — again, when one sees that the indivi- 

 dual of Sorastrum spimdosum is often " bilobate," as repre- 

 sented in fig. 5 {a), perhaps from atrophy, as the reverse be- 

 comes the case in robust individuals (b, c, d), one cannot help 

 thinking that, in these two conditions combined, it is just pos- 

 sible that Meneghini's Sorastrum echinatum (Synops. in Linn, 

 xiv. p. 238. n. 4) of 1840 may be Nageli's S. s^imdos2im 

 (Einz. Alg.) of 1849 and Rabenhorst's >S'. hidentatum (Flor. 

 Europ. Alg.) of 1868 — all phases of one and the same in- 

 dividual which I have often seen manifested among the 

 different groups of the Sorastrum under consideration, and 

 therefore trifling differences which I do not think warrant the 

 separation. 



If priority of notice gives precedence, then it seems to me 

 that Meneghini's name of Sjjhcei-astrum echinatum for this 

 little plant should be retained. Klitzing, also, has changed 

 " SjyJicerastrum " to " Sorastrwn," or at all events adopted 

 Nageli's appellation (which is the latter) for the genus. 



Making a " heap " of it, instead of a " sphere," seems to me 

 like requiring a little more when enough has been attained, or 

 risking the substance for the shadow — a course which too 

 often breaks down the memory with disgust, and, if continued, 

 must sooner or later be altogether suicidal to natural history. 



There is one point, however, in which all the representations 

 and descriptions of this little organism appear to be deficient, 

 viz. in the mention of a stipes (fig. 2 a) , whose presence, as 

 my figures will show, necessitates the addition of " stipitate " 

 to its cuneate outline. 



From the triangular form of, and spines on, the individual 

 of Sorastrum, resembling especially Staurastrum avicula and 

 S. dejectum (Ealfs, Desmid. pi. 23 and pi. 20, figs. 11 & 5 re- 

 spectively), it has hitherto been placed among the Desmidiese ; 

 but the latter, although much about the same size as the 

 cuneate individual of Sorastrum, appears in pairs, united by a 



