Algse of the English Lake District. By Wm. West. 727 
C. Portianum Arch. B., Bo., H., B , Bt., Hk., Blea Tarn, in 
Borrowdale. 
C. reniforme (Balfs.) Arch. B., Hk., Bassenthwaite Water. 
War, compressum Nordst. (Freshw. Alg. of New Zeal, 
and Austr., p. 46, t. 5, f. 5). 
Long. 48 /r ; lat. 47 yu, ; lat. isthm. 13 yu, ; crass. 24 ya. 
Hk. 
C. Logiense Biss. Frequent. 
C. punctulatum Breb. B., H., Crummock Water, Trough at 
Ambleside. 
0. subpunctulatum Nordst. var. Borgesenii West. 
Forma semicellulis ad apices leviter convexis, in medio 
granulis paullo majoribus (7 periphericis et 1 centrali). 
Long. 33 ya; lat. 30 //-; lat. isthm. 11 //,; crass. 19 ya. 
Fig. 18. 0., Hk., Langdale. 
The centre granules in var. Borgesenii West (Contrib. Freshw. 
Alg. of W. Ireland, plate 21, fig. 9) have been drawn like the others 
by the artist ; they should have been made larger. 
C. Blyttii Wille. Hp., Wythburn. 
Forma paullo minor. Lat. 10 ya; crass. 7 ya. H. (at 
2400 ft.). 
C. orthostichum Lund. 
War. pumilum Lund. (Desm. Suec., p. 25, t. ii. f. 10). 
Long. 25 ya; lat. 20 ya ; lat. isthm. 5 ya ; crass, 12*5 ya. 
Bo., H. 
C. Botrytis (Bory) Menegh. Very frequent. 
G. Turpinii Breb. var. Lundellii Gutw. Near Cockermouth. 
C. vexatum sp. n. Fig. 33. 
O. mediocre, paullo longius quam latius, profunde con- 
strictum, sinu lineari extremo ampliato; semicellulse sub- 
trapezicse, lateribus convexis, angulis inferioribus rotundatis et 
minute undulatis, angulos superiores versus cum undulis 
majoribus, dorso truncato et levissime subundulato ; a vertice 
vism oblongo-ellipticm, medio glabro tumidrn ; a latere visse 
subcirculares ; membrana grosse granulata, granulis sub- 
concentrice et subradiatim ordinatis, glabra ad medium; 
pyrenoidibus binis. 
Long. 41-43 ya; lat. 36-38 yu,; lat. isthm. 13 ’5-14 ya; 
crass. 20-21 y a. Ambleside, not uncommon. 
At first sight this appears like some forms of G. Botrytis (Bory) 
Menegh., but it is much smaller, it has truncate and almost smooth 
apices, the lateral undulations are larger towards the apex as in 
G. Quasillus Lund., and the vertical view has a glabrous inflated 
centre. It differs from G. Quasillus Lund, and G. subquasillus Boldt 
in its smaller size and in the smaller central inflation of the vertical 
view being without undulations, as well as in other particulars. It 
