342 MR. S. L. GHOSE ON A COLLECTION OF 
32. AULOSIRA FERTILISSIMA, sp. n. (Pl. 31. fig. 9.) 
Strato expanso, sordide aeruginoso, membranaceo; trichomatibus rectis vel 
leviter flexuosis, parallelis vel dense intricatis, raro pseudo-ramosis ; cellulis 
6-11 y latis et 7-10 u longis, in statu juvenali eylindrieis denique doliformibus, 
protoplasmate granuloso ; vaginis crassis, primum gelatinosis et hyalinis deinde 
firmis et fuscescentibus ; heterocystis intercalaribus, oblongis vel ellipticis, 
8-9 u latis et 10-14 p longis, contentu homogeneo ; sporis in catenis longis 
dispositis cum cellulis moribundis deplanatis alternantibus, plerumque oblongo- 
ellipticis interdum propter compressione angulosis, dimensione 18-24 u X 11— 
13 a ; epispora plerumque firma levi, interdum fusca. 
Hab. Lahore, in one of the broad water-courses of the Shalamar Gardens, 
on decaying leaves of Velumbium speciosum; October-March. 
There are two features peculiar to this species. First, at the time of 
reproduction the whole of the trichome becomes fertile and the cell or cells 
situated between the spores either slowly die off or become changed into 
dark-green biconcave cells. A fertile filament then consists of spores, 
between which dead coloured dises are seen. This resembles what has been 
figured by Borzi in connection with spore-formation in Zolypothria Wart- 
manna Rabh. (Nuovo Giorn. Bot. Ital., xi. 1879, pl. 10. fig. 15, copied in 
my figure, Pl. 31. fig. 10). Secondly, in rare cases the filaments are seen to 
produce very short pseudo-branches, resembling those of Plectonema, which, 
however, does not possess any heterocysts. Ata level with one of the con- 
cave cells the mucilage sheath swells up and one part of the filament grows 
out into a short pseudo-branch (Pl. 31. fig. 9, 7, e). The alga cannot be 
referred to Tolypothrix because there is no heterocyst at the point of ramifi- 
cation, nor to Scytonema, as the branches are always single. For the present 
the alga seems to find its best place in the genus Aulosira in spite of the 
occasional ramification, but investigation of further material may show that 
it is a peculiar stage of an alga like Tolypothrie (which is sometimes very 
little branched) or a distinet genus. 
33. MICROCHÆTE CALOTRICHOIDES, Hansg., in Beihefte z. Bot. Centralbl.. 
xviii. p. 494. 
Diam. fil.= 8-124; diam. trich.= 6; diam. heterocyst.= 6 4; long. 
heterocyst. = 7-8 y. 
Hab. Lahore, adhering to the surface of submerged leaves in a stagnant 
pool of water, intermingled with (ÆEdogonium and other alow; October- 
March. 
SCYTONEMATACEZÆ. 
34. Scyronema Frirennm*, sp.n. (Pl. 81. fig. 11.) 
Strato floccoso, viride-fusco ; filamentis tenuibus, elongatis, 15-20 u crassis; 
trichomatibus 7-8 u crassis, articulis plerumque latitudine duplo longioribus ; 
* This species is named after Prof. F. E. Fritch, D.Sc., of the East London College, 
whose generous help was very valuable to me during this piece of work. 
