NOTES ON FEESHWATER ALG.E. 331 



but one of the DiatomacecB. We possess the original specimens 

 from which Turner described the species, and find both his de- 

 scription and figures to be lacking in accuracy. The rows of spines 

 which he described and figured are but markings on the valve, and 

 by varying the focus they can be seen somewhat as he drew them 

 (though less exaggerated). He says, '* formingjlong filaments"; 

 the diatom is probably a species of Desmogonium, and occurs in 

 filaments, some of which are branched. Also "spines arranged 

 longitudinally in six linear series " is not correct, there being only 

 four series of markings on the valve. 



5. Spirot^nia minuta Thur. var. eboracensis, var. n. Var. cel- 

 lulis brevioribus, apicibus subrotundatis, anfractibus chlorophori 

 3-4. Long. 30-32 fx ; lat. 7-8 /x. 



Hab. Cam Fell, W. Yorkshire, not uncommon amongst Cylin- 

 drocystis crassa, Peniimi digitus, Hyalotheca dissiliens, &c., in peat bogs. 



This variety is relatively shorter in proportion to its breadth 

 than the type ; it has also blunter ends and more turns of the 

 chromatophore. The figures given by Liitkemiiller (Oesterr. botan. 

 Zeitschr. 1895, t. i. f. 21) also show more turns of the chromatophore 

 (up to 4|-) than are described for this species. 



6. Spirotsenia fusiformis, sp. n. S. parva, elongata; cellulis 

 rectis vel ssepe leviter obiiquis, diametro 10-12-plo longioribus, 

 cylindrico-fusiformibus, apices versus attenuatis, apicibus acutis sed 

 rotundatis ; chlorophoris singulis, parietalibus, subnregulariter dis- 

 positis, de polo ad polum extensis, circiter anfractu dimidio. Long. 

 42-58 /x; lat. 4-3-4-6 /x. 



Hab. In peaty pools, amongst Sphagnum cuspidatum var. plu- 

 mosum, Cowgill Wold Moss, Widdale Fell, W. Yorkshire. 



The cells were solitary or in pairs (after division), and occurred 

 somewhat sparsely among a large quantity of Arthrodesmus Incus. 

 The cells were evidently surrounded by an almost invisible mucus, 

 the extent of which could not readily be ascertained on account of 

 its extreme transparency. It was very difficult to determine the 

 precise nature of the chromatophore, because of its irregularity and 

 the small size of the plant ; it only made from half to three-quarters 

 of a turn, and the protoplasm (outside the chromatophore) contained 

 some large granules. 



It is distinguished from 8. tenerrhna Arch. (= S. gracillima Arch.) 

 by its greater diameter, its comparatively shorter cells, and its very 

 different chromatophore. 



7. Spirotaenia turfosa, sp. n. S. mediocris ; cellulis sub- 

 cylindricis, elongatis, subrectis vel leviter curvatis, diametro circiter 

 12-plo longioribus, utroque polo gradatim attenuatis, apicibus ob- 

 tusis; chlorophoris singulis, parietalibus, anfractibus l|-2,pyrenoidi- 

 bus minutis et sparsis. Long. 100-102 /x ; lat. 7'5-8-5 /x; lat. apic. 

 circ. 4 /x. 



Hab. In peaty pools, Ilkley, W. Yorkshire. 

 This appears to come nearest to 8. parvula Arch., but is of much 

 larger size, is proportionately longer, has more rounded and rela- 



2 a 2 



