84 THE JOURNAL OF BOTANY 



Kiitz.] , Epithemia turgida (Ehrenb.) Klitz., Surirella ovalis Breb. 

 var. angusta (Kiitz.) V. Heurck. - 



Fragments of two species of Synedra were also present, viz. 

 S. Acus (Kiitz.) Grun. and S. Ulna (Nitzsch) Ehrenb. 



III. — New and Eare British Alg^. 



1. Stichococcus scopulinus Hazen, "Ulotrich. and Chaetoph. 

 of tlie United States," Memoirs Torr. Bot. Club, xi. no. 2, 1902, 

 p. 161, t. 22, f. 4-6. This species was collected by Mr. W. B. 

 Grove on wet stones at Studley, Warwickshire, in December, 1909. 

 It seems to be a very characteristic species, having cells 3-3-5 /x 

 in diameter, and up to 10 (or even 12) times longer than broad. 

 It has not previously been recorded for the British Islands. 



2. Closterium tumidum Johnson in Bull. Torr. Bot. Club, 

 xxii. n. 7, 1895, p. 291, t. 239, f. 4 ; W. & G. S. West, Monogr. 

 Brit. Desm. i. 1904, p. 156, t. 19, f. 15-18. The characters of this 

 species were drawn up to include, amongst other forms, the 

 Desmid originally described and figured by Ealfs as " Closterium 

 Cornu Ehrenb. var. /5" (vide Ralfs, Brit. Desm. 1848, p. 176, t. 30, 

 f. 6a-e). Of this form Ralfs figured the zygospores, and these are 



generally accepted as representing the 

 zygospores of C. tumidum. They are 

 subrectangular, with retuse sides and 

 produced angles. 



Quite recently Mr. W. B. Grove 

 collected in Warwickshire numbers of 

 rather small forms of G. tumidum, agree- 

 ing exactly with that figured by W. & 

 G. S. West, I. c. pi. 19, f. 15. Many of 

 these had conjugated and the zygo- 

 _ spores were subglobose. It seems de- 



Fig. l.-Clo.<.n«»Umn/*m f^^ble, therefore, to regard this small 

 Johns, var. ^ili(tro>^pora, var. n. form as a distmct variety. 

 A, vegetative cell; B, zygospore, Var. SPH^ROSPORA, var. n. (Fig. 1). 



X 500. Var. cellulis parvis et brevibus ; zygo- 



sporis subglobosis vel ellipsoideo-glo- 

 bosis. Long. cell. 48-66 /a, lat. 8-8-5 /x ; lat. apic. 3-4 /x ; diam. 

 zygosp. 23-5-26 /x. 



Hah. Earlswood, Warwickshire, March, 1910. 



3. Pleurococcus rufescens (Kiitz.) Breb. This species of 

 Pleurococcus is exceedingly rare in the British Islands. In October, 

 1907, Mr. W. B. Grove collected very fine specimens attached to 

 wood in a rain-water tank at Bewdley, in Worcestershire. Diam. 

 cell. 11-5-17 /x. 



4. Richteriella botryoides (Schmidle) Lemm. in Hedwigia, 

 xxxvii. 1898, p. 306, t. 10, f. 1-6. This limnetic Alga occurred in 

 small quantity associated with Actinastrum Hantzschii in the 

 surface waters of the canal at Lifford, Worcestershire, in October, 

 1910. It is quite possible that this and other allied Algae are 



