NOTES ON FRESHWATER ALG^. 333 



to find they did not agree with Joshua's description and figures in 

 several particulars, but that they agreed much better with D. egregium 

 W. B. Turner. Turner's species is undoubtedly the same as that 

 of Joshua, and is more correctly described and figured, yet Joshua's 

 name has the priority, and we must regard I), egregium as a synonym 

 of Pleurotmnium amiulatum. The somewhat rounded, smooth areas 

 C annuli " of Turner) are the thinnest parts of the cell-membrane, 

 as in the case of Pleurotmihim trochiscum West & G. S. West; they 

 are arranged in almost straight or somewhat oblique longitudinal 

 series, not quite so irregular as those figured by Turner, and of 

 somewhat greater area also. Turner's fig. 15 is more correct than 

 his fig. 14 or than that of Joshua, in the light of the specimens we 

 have examined. 



15. DociDiuM cosTATUM Wolle, Desm. U. S. 53, t. x. f. 2 (1884). 

 This "species" is not a Desmid, but a portion of some aquatic 

 arthropod. We found many of these structures, corresponding to 

 Wolle's " semicells," in material received from him. He also 

 remarks under his description (I.e.) : "The specimens which came 

 under my observation were not vegetative — too old ; this species 

 needs verification." Yet his figures are coloured green ! 



16. EuASTRUM ROSTRATUM Kalfs, var. PRiEMORsuM Nordst. in 

 K. Vet.-Akad. Handl. xxii. 34, pi. iii. f. 7 (1888). A form almost 

 agreeing with that figured by Borge, Austral. Siissw.-alg., Bih. till 

 K. Sv. Vet.-Akad. Handl. Bd. 22, Afd. iii. no. 9, 1896, t. i. f. 13, 

 but without the two scrobiculations on each semicell. 



Hab. Eangoon, British Burmah. 



17. EuASTRUM TuRNERi De Wildem. Obs. critiq. quelq. espec. 

 Desmid., Ann. d. 1. soc. belg. de microsc. [Memoires] , t. xviii. 



1894. Under this name M. de Wildeman unites E. splnosum Wolle, 

 E. Nordstedtimiitm Wolle, and E. quincunciale W. B. Turner. Why 

 should a new name be created for a species already possessing one ? 

 Apart from this, there is already an Enastrum Turneri West in 

 Journ. Linn. Soc. hot. xxix. 141, pi. xx. f. 18 (1892). We have 

 already proved E. Nordstecltianum Wolle to be E. evolutum (Nordst.) 

 West & G. S. West (Cfr. Journ. Linn. Soc. bot. xxxiii. 290, fig. 

 xylogr. 1, 1898). E. sjnnosum Wolle may be a form of this, or may 

 not, Wolle's figures being too indistinct and inaccurate to determine 

 this point. The figures of E. quincunciale given by W. B. Turner 

 show that it is not a form of E. evolutum, the surface markings 

 being so different. 



18. CosMARiuM DOLiFORME West & G. S. West in Trans. Linn. 

 Soc. bot. ser. 2, v. 246, pi. xv. f. 16 (1896). Schmidle, in Nuova 

 Notarisia, 1897, 70, states that this is the same as Dysphinctium 

 parvulum var. imdulatum Schmidle in Oesterr. botan. Zeitschr. 



1895, 348, t. XV. f. 7. We are quite sure that C. dolifonne has no 

 relationship to C. parvulum, being much nearer to C. pyramidatum. 

 We may, however, state that D. parvulum var. undulatum is identical 

 with C. tetragonum var. pumilum West in Journ. Roy. Micr. Soc. 5, 

 pi. i. f. 19, 1894, although larger, and we are now of the opinion 

 that the latter should be placed under C. parvulum. 



