68 SOME EECENTLY PUBLISHED DESMIDlEiE. 



Oberoster. 1892, p. 21, taf. viii. f. 9 ; C. ochthodes forma amceba- 

 grcmnlosa Schmidle, Einz. Alg. Bern. Alp., Heda-Ujia, 1894, p. 92, 

 taf. vi. f. 9). These three forms of C. ochthodes do not differ from 

 one another sufficiently to admit of any separation, and they must 

 therefore be placed together under the earlier name. 



CosMARiuM HUMiLE Gay, var. glabrum Gutw. [Matenjaly do Florxj 

 Glonow Galicyi, Krakow, 1892, p. 27, t. iii. f. 14). This is only a 

 form of C. subdriattim Nordst. (Wittr. & Nordst. Alg. Exsicc. no. 977, 

 1889). 



CosMARiuM CALGAREUM Wittr. as figured by Johnson (Some new 

 and rare Desmids of U.S., i.. Bull, of Torrey Bot. Club, July, 1894, 

 pi. 211, f. 13). Johnson states that it "agrees well with Wittrock's 

 description and figures," except in the central granules. We should 

 say that fig. 13 « agrees with Wittrock's figure chiefly in the central 

 circle of granules, but even this is relatively much larger. The 

 form of the semi-cells, the depth of the sinus and consequent 

 breadth of the isthmus, as well as the disposition of the granules, 

 seem to us very different from those of Wittrock's C. calcareum. 



CosMARiuM RECTANGULUM Sclimidle (Aus der Chlorophyceen- 

 Flora der Torfstiche zu Virnheim, Fl. oder ally. Bot. Zeituny, 

 1894, p. 57, taf. vii. f. 23). Schmidle has described a species 

 under the above name without noticing that this name had already 

 been monopolised by Keinsch, the latter having described a C. 

 rectanyuluiii (Keiusch, Contrih. Aly. et Fung. taf. x. f. 9) in 1875. 

 Hence we propose to call Schmidle's species C. Schmidlei. 



CosMARiuM TRiLOBULATUM Eeiiisch, var. ExcAVATUM Eichler & 

 Gutw. (Nonn. Alg. Nov., Krak. Akad. 1894, p. 4, t. iv. f. 8). This 

 is most certainly a variety of Cosmarium venustum (Breb.) Arch., so 

 we propose to name it C. venustum var. excavatum. 



Cosmarium difficile Liitkemiiller (Desmid. aus der Umgeb. des 

 Atters. Oberostei'., Verhand. Zool.-Bot. Gesellsch. Wien, 1892, p. 551, 

 taf. viii. f. 3) and var. sublave Liitk. correspond exactly in outline 

 to one of the commonest forms of Cosmarium Memyhinil Breb., met 

 with in the British Isles and North America, and specimens 

 received from Dr. Liitkemuller were by no means constant with 

 regard to the number and position, or even presence, of the minute 

 punctulations he describes, and even if present in some examples, 

 they are not sufficient for a specific distinction. 



Cosmarium minutum Benu. (Freshw. Alg. and Schizophyceffi of 

 S.W. Surrey, Journ. R. M. S., Feb. 1892. p. 10, pi. ii. f. 11). This 

 is probably a small form of C. polyyonum Nag., with more acute 

 lateral angles ; but the lateral and vertical views should have been 

 given. However, as there is a C. viinutum. Delp. [Desm. Suhalp. 

 1878), the name will in any case have to be changed. 



Cosmarium minutissimum Heimerl (Desmid. alp., Verh. Zool.-Bot. 

 Gesellsch. Wien, 1891, p. 600, taf. v. fig. 14). Heimerl describes a 

 species under this name, but the name had previously been applied 

 to another plant by Archer {Q. J. M. S., 1877, p. 194; Cooke, 

 Brit. Desm. p. 91); we therefore propose to name Heimerl's species 

 C. Heimerlii. 



Xanthidium Tylerianum West (List of Desm. from Massa- 



