150 W. Ii. TURNER, FRESH-WATEB AI.ii.E OF BA8T IXDIA. 



Gen. 25. Didymoprium, Kutzixg. 



(Phycol. Generalis p. 166, 1843: Sp. Alg. p. 189, 1849; Kalks Br. Desm. p. 55, 1848; mat. char.; Desmi- 

 dium sect. a, non be, De Bary Conj. p. 76, 1858). Desmi di? sp. auetorum restricti; cellulae plus minus com- 



pressse, saepe 2-anguIatae, sine processubus intercellularibus. 



1. D. cylindricutn (Grev.) Ralfs (in Annals N. H. vol. XVI, p. 10, 1845; Desmidium 

 cylindricum, Ghev. Scot. Crypt. Fl. p. 293, 1827; Kutz. Synops. Diat. in Linnaea p. 

 614 (separ. p. 86!), 1833; Ralfs in Annals vol. XI, p. 373, t. VIII, f. 1, 1843; Me- 

 negh. Synops. p. 204, 1840; et auet. nonnull.; Arthrodesmusf cylindricus Ehkb. Inf. 

 p. 142, 1838; Hyalotheca cylindrica, Ehr. Kurze Nachrichte, 1840; Desmidium com- 

 pressum Corda, Obs. Micr. p. 18 (p. 203?), 1840; Didymoprium Grevillei, Kutz, Phvc- 

 Gen. p. 166, 1843; Phyc. Gerrn. p. 141, 1845; Ralfs Br. Desm. p. 57, t. II, 1848). 



Long. 32, lat. 54 u. 

 One specimen only seen. 

 Northern India, J. S. 



2. D. graciliceps, Nordst. (Lagerii. Bidr. Am. Desm. Fl. p. 228, t. 27, f. 2, 3, 1885, 

 as Desmidium graciliceps; Desm. quadratum Nordst. fi graciliceps Nordst. W. and 

 N. Alg. Éxsicc. 367 et 554; Didymoprium? graciliceps, Nordst., Alg. N. Z. p. 25, 1888)- 



Long. 18, lat. 2&, lat, apie. 23. r. «. 



Central India; only 4 cells seen, apparently not conimon. 

 [f. iiitermedia. This is the D. quadratum of Joshua, 1. c. p. 635, t. XXII, f. 3. Bri- 

 tish Burmah, W. J.] 



Xote. I would deprecate the total fusion of this genus with its near relative 

 Desmidium, except perhaps as a sub-genus. To me the greatest difference is the fact 

 of Didymoprium being without the small intercellular connecting processes so eharac- 

 teristic of Desmidium; I have therefore proposed the fact of their absence as the chief 

 ground of the restoration of Kutzing's genus to its pristine rank, although with altered 

 characters. It is true that the apical j>arts of the cellules are not always totally in 

 contact, partly only touching each other, but still apical connecting eushions' are 

 wanting. Cfr Hauptfleisch, Zell. Desm. t, I, f. 39, 40, 45, 52. 



Gen. 26. Phymatodocis, Nordst. 



(Nonn. Alg. Brås. p. ID. 1877; Hedwigia, p. 70, 1878). 



Not yet observed in India, 



On t, XXI, f. 9 are figured 2 cells, one of which seems abnormally jtroduccd 

 at the angles, after Wallich Mscr. No. 326. Di;. Wallich styles it a Je ne sais quoi, 

 and places it among the lower Alga i . I at first deemed it to be a compressed or 2- 

 angled form of Desmidium Baileyi, analogous to the corresponding form in D. aj>to- 

 gonum. However, it has been suggested to me that these doubtful cells possibly may 

 be those of a Phymatodocis *]>.; perhaps abnormal? certainly in an abnorma] position. 



