Algse of the English Lake District. Bg Win. West. 731 
8. furcatum (Ehrnb.) Breb. S., L. 
var. armigerum (Breb.) Babb. W., C., Hk. 
*8. senarium (Ehrnb.) Balfs. Bn. 
S. Beinschii Boy. Sk., Hk. 
S. hirsutum (Ehrnb.) Breb. W., B., H., Bt., C., Hk., Blea 
Tarn in Borrowdale. 
S. pilosum (Nag.) Arch. Bn., C., Bo., Hk., Wythbnrn, Black 
Sail Pass. 
8. Brebissonii Arch. var. brevispinum var. n. Fig. 26. 
Yar. spinis brevioribus et validioribns. 
Long. 49 /a ; lat. s. spin. 42*5 /a ; lat. c. spin. 45 /a ; 
lat. isthm. 17*5 /a. B. 
8. Hystrix Balfs. B. 
S. teliferum Balfs. Frequent. 
S. polytrichum (Perty) Babh. Bn. 
8. asperum Breb. C. 
8. muticum Breb. S., Kirk Fell. 
8. orhiculare (Ehrnb.) Balfs. Common, 
forma major. 
Long 61 /a; lat. 50 /a; lat. isthm. 17*5 /a. Bo. 
*var. extensum Nordst. A small form. 
Long. 38-39 /a; lat. 25*5-28 /a; lat. isthm. 8-10 /a. 
B., Lake Side, Stye Head Tarn. 
var. depressum Boy. et Biss. Bn., Hk. 
8. Bieneanum Babh. B. 
8. Eibernicum West. 
Forma membrana irregulariter punctata. 
Long. 63 /a; lat. 56 /a ; lat. isth. 19*5 /a. L. 
S. ellipticum sp. n. Fig. 28. 
S. mediocre, circiter 1^-plo longius quam latius, modice con- 
strictum, sinu acutangulo et ampliato ; semicellulm ellipticse ; 
a vertice visae trigonae lateribus leviter convexis, angulis late 
rotundatis ; membrana laevis ; pyrenoidibus singulis magnis. 
Long. 42*5-46 /a ; lat. 29-30 /a ; lat. isthm. 13-15 /a. Bo. 
The front view is similar in form to S. turgescens Be Not., but the 
membrane is smooth and the vertical view is different. It differs from 
8. vesiculatum Wolle (Freshw. Alg. of U.S., p. 42, pi. liv. f. 6, 7) in 
its broader sinus and elliptical semicells. 
8. Kjellmani Wille. Sk., H., Bt., Blea Tarn in Borrowdale. 
8. pygmseum Breb. Frequent. 
fi>. turgescens Be Not. Trough at Ambleside, Buttermere, Blea 
Tarn in Borrowdale. 
8. muricatum Breb. Bo., B., Hp., Kirk Fell. 
A form of this species occurred at an elevation of 2400 ft. on 
Helvellyn, which was just as long as broad, and very similar to figs. 
19 and 20, tab. vi. in Nordst., Besmidieer fran Bornholm. 
3 d 2 
