Freshwater Algae of S. of England. Bg W. & G. S. West. 487 
strictum, sinu brevi et aperto ; semicellulae subtrapeziformes, 
angulis super ioribus oblique truncatis, lateribus divergenti- 
bus sursum, apicibus latis, rectis vel levissime retusis ; a latere 
visa? subcirculares ; a vertice visae elliptico-oblongae, polis sub- 
acutis, medio utrobique leviter tumidae, polos versus utrobique 
papilla instructae ; pyrenoidibus singulis. 
Long. 10*5-11 *5 /x ; lat. 11-13-5 g ; lat. isthm. 5- 
5*5 jjl] crass. 6*5 /a. III. Th. 
We also have this minute species in immense quantity among 
Sphagnum from Mossdale Moor, Widdale Fell, N. Yorks. It is most 
nearly related to some forms of C. Heimerlii in vertical view, but the 
front view is quite distinct. The figures are all taken from Yorkshire 
specimens. 
37. G. Begnellii Wille. I. Ep. II. Ha. III. Bi. VII. S. 
38. G. impressulum Elfv. I. Ep. II. U. III. Eg., Mp. VII. 8. 
VIII. Tm. 
39. G venustum (Breb.) Arch. VI. N. VIT. D. VIII. G., 
K, L. 
Yar. majus Wittr. III. Th. VI. N. 
40. G. Iseve Babenh. I. Ep. IY. He. YIIL T. 
Yar. septentrionale Wille. I. Ep. II. Wh. III. Pu. 
41. G. Meneghinii Breb. General. 
Forma octangularis Wille. II. Wh. III. B., Di., M., 
Mp., Wi. IV. Ks. Y. Go. VIII. G., P., T. 
Yar. Wollei Lagerh. VII. D. 
*42. G. difficile Liitkem. III. Th. VI. N. VIII. T. 
*Var. sublaeve Liitkem. VIII. T., W. 
*43. G. umbilicatum Liitkem. II. Wh., abundant. 
44. G. concinnum (Babenh.) Reinsch. III. Pu., Th. 
45. G. obliquum Nordst. III. C. 
46. G. Begnesii Beinsch. III. Th. (with zygospores), Pu., abun- 
dant. VI. N. 
47. G. montanum Schmidle ( G.Bseudoregnesii West & G. 8. West). 
I. Ep. 
*48. G. Novae Semliae Wille var. sibiricum Boldt. VI. N., very 
abundant, June 1897. 
49. G. cgmatonotophorum West. III. Th. VI. N. 
*50. G. Sinostegos 8chaarsm. var. obtusius Gutw. III. Pu. 
51. C. adoxum sp. n. (PI. VII. fig. 24.) 
C. minutissimum, paullo longius quam latum, profunde 
constrictum, sinu lineari ; semicellulae late pyramidato-trapezi- 
formes, angulis basalibus oblique rotundo-truncatis et leviter 
divergentibus, lateribus (superioribus) subrectis vel levissime 
retusis, apicibus late truncatis rectisque ; a vertice visae ellip- 
2 M 
1897 
