Freshwater Algse of North Wales. By Wm. West. 295 
and Wolle describe tbe end view as 7 (rarely 6 or 8) rayed ; the 
forms from Capel Curig are almost all 8-rayed. 
S. prohoseideum Breb. Llyn Ogwen. 
var. sunaLABRUM nov. var. Fig. 35. 
Var. margine undulato nec spinis truncatis vestitis, 
radii apicibus integris. 
This differs from the type in being undulately rough and not 
adorned with truncate spines, as well as in the entire apices of the 
processes. C. 
S. controversum Breb. D., S., P. Fig. 22. 
A figure of a variety of this variable species is given. 
S. aculeatum Meneg. P. 
S. DUBiuM nov. sp. Fig. 28. 
S. submagnum, latius quam longum, scabro-granulatum, 
semicellulis fusiformibus, constrictione profunda, radiis pro- 
ductis tricuspidatis et inflexis, a vertice triangulare, ad basem 
semicellulaB cum annulo singulo granulorum. 
Long. 40 fx] lat. 70 lat. isth. 13 [x. 
This species is nearly twice as broad as long, deeply constricted 
with rough granules, processes indexed, granulate and tricuspidate, 
semicells somewhat fusiform, base annularly granulate, vertical view 
triangular. C. 
This will no doubt prove a controversial species ; it is near 
8. Manfeldtii Delp., but smaller and with thicker processes ; it is 
also more regularly granulate. It also comes near 8. pseudosehaldi 
Wille, but lacks the basal inflation and the bifurcate spines. The 
front view is like 8. vestitum Kalfs, but the end view has not the 
characteristic spiny adornments of the sides of that species. It is not 
like 8. 8ebaldi Eeinsch, but the end view does approach the var. 
ornatwn Nord., as well as the form novizelandica Nord. of the latter 
variety, yet the centre of the concave sides of the end is much 
rougher, and the processes are thicker than the above-mentioned 
form as well as shorter than those of the var. ornatum, and more 
indexed than either. It also has some resemblance to 8. hifurcum 
Josh., but the arms are more indexed, and the outline is more 
regular. It is also relatively shorter than all these species except 
8. vestitum and one of the original figures of 8. hifurcum. 
8. oxyacanthum Arch. C., B. 
8. 8ebaldi Eeinsch, var. ornatum Nord. C. 
8. eustephanum (Ehrb.) Ealfs. C. 
8. sexangulare Buln. C. 
