344 MR. S. L. GHOSE ON A COLLECTION OF 
branches, which may arise singly at the base of an heterocyst as in 
Tolypothrix or in pairs as in Seytonema. In addition to the points of dis- 
tinction between it and the species under discussion already mentioned in my 
earlier paper (loc. cit. p. 38), another great difference lies in the absence of 
true branches in C. lahorense, although a thorough search for them has been 
instituted. In view of this fact, C. lahorense can hardly be included in the 
Stigonemataceæ, which are characterised by their true branching, but should 
rather be referred to the Seytonematacew, as Forti (in De Toni, Syll. Alg. v. 
p. 540) has already done for Schmidle’s species. Whether this last is justified 
is, however, doubtful, since according to Schmidle’s description and figures 
(Loc. cit.) the bulk of the branching is true. A re-investigation of C. indicum 
is much to be desired. Should the true branching prove to be a regular and 
frequent feature, the species here described will have to be referred to a 
distinct genus of the Scytonemataceæ. A marked point of resemblance to 
Schmidle’s form lies in the Camptothrix-like growth of the curved filaments 
with median heterocysts in C. lahorense. This and the occurrence of both 
single and geminate branches are at present the chief grounds for referring 
the two species to the same genus. 
38. ToLYPOTHRIX CAMPYLONEMOIDES, sp. n. (PI. 81. fig. 12.) 
Strato obscure cæruleo-fusco, tenui papyraceo; filamentis curvatis, 10-12 u 
crassis: pseudo-ramis irregularibus, sparsis, brevibus, erecto-patentibus, 
solitariis vel raro geminatis ; vaginis tenuibus, fragilibus, in statu juvenali 
achrois deinde luteis vel fuscis; trichomatibus 8-10 u crassis, torulosis : 
articulis diametro brevioribus, protoplasmate granuloso ; heterocystis solitariis, 
terminalibus vel intercalaribus, subglobosis, circa 11 p latis et 9:5 g longis. 
Hab. Lahore, on trunks of Acacia modesta, associated with many other blue- 
green algæ, during the months of August to October. 
In dry weather the stratum resembles a thin sealy bark, but after a little 
rain it becomes slimy and numerous hormogonia glide out of their sheaths. 
Some of these hormogonia are only one- or two-celled. If the weather 
remains moist and favourable, these hormogonia show active growth and 
form a delicate stratum by arranging themselves parallel to one another. 
They slowly secrete a sheath, which is at first very delicate and hyaline, but as 
the weather becomes drier, acquires a firmer character and takes on a yellowish- 
brown colour. At the same time the surface filaments become crescentic in 
shape owing to the two ends curving upwards. Heteroeysts may arise in 
very young filaments or in mature ones. Pseudo-branches are few and are 
produced in connection with the heterocysts or in relation to the formation 
of concave discs. They are single or rarely geminate. In summer the 
filaments break up into many pieces, which may separate as sheathed 
** pseudo-hormogonia,” resembling those mentioned by Schmidle in Hedwigia, 
xxxix. 1900, p. 181, in Campylonema indicum. (Pl. 81. fig. 12, b.) 
