THE ALGA-FLORA OF CAMBRIDGESHIRE. 265 
being to the Tetrasporee, but this I cannot agree with. The 
bees are excessively thin, 190-260 p = eciee and are attenu- 
ated to a very fine apex, near which minute branches or spurs are 
osbaicallly developed. In addition to fvetiteniag the presence of 
zoospores, Lagerheim, in Nuova Notarisia, 1890, 231, says ‘nucleus 
singulus,’’ and, as this plant is undoubted! a member of the 
Chroococcaces, it would appear that at least one member of this 
order, and therefore at least one blue-green alga, is possessed of a 
definite nucleus. I may mention that one of the most conspicuous 
features to be noticed is a clear space in the centre of each cell, as 
though for the retention of a nucleus , and, in fact, this plant appears 
any of the Be phvics 
Subfam. Eucnroococcaces. 
253. GuaotHEcE conrLuENS Niig. 2. Dernford Fen, 1 mile §. 
of Shelford. 5. Chippenham Fen. 
254, ApHANoTHECE microscopica Nig. 5. Chippenham Fen. 
. Syn pore pane Schroter. Syn. S. crassus Arch. 5. 
Chinen Pat. Wicken Fen. 
256. S. roseo-purpureus, sp.n. (Pl. 895, fig. 10). 8. cellulis 
inutis, singulis vel geminis, oblongis et ’sube ylindricis, polis 
obiane rotundatis, diametro ad 1}-plo longioribus ; cytioplasmate 
roseo-purpureo cum granulis conspicuis paucis. Long. cell. 8-8- 
9-5 pw; lat. cell. 3-6-6 
5. Wicken Fen, in ditches, — Mougeotia sp. 
This occurred in imm mbers in several ditches at the 
margins of Wicken Fen; it ery chaructriticaly short cells, is rarely 
much longer than broad, and is of a marked rose- ram colour, the 
few large granules in each cell being dark and conspic 
257. Guaucocystis NosrocurnearuM Itzigsh. 6. sone Pits, 
Ely. ; 
258. Merismopepia nyauina Kitz. 6. Roswell Pits, Ely. 
oe M. viotacea (Bréb.) Kitz. 5. Wicken Fen. 
ie GLAUCA Core b.) Nag. 38. Trumpington ; Lord’s 
iaiee: mpole Park. 5. Wicken Fen. 7, ae ds §. of March. 
8. trea fout River, forvecn March and Guyhirn 
261. M. puncrata Meyen. 8. Guyhirne, in ees 
*962. M. evecans A. Braun. 5. Wicken Fen. Diam. cell. 6-5— 
9:5 pw. This fine species, much the largest of the Wee ae only 
previously been met with from a few localities in Germany. The 
cells are somewhat angular by compression, and are of a brilliant 
blue-green colour. The families attain a very large size, and 
tain more numerous cells than those of any other species of 
Merismopedia ; those observed were composed of 544-1856 cells, 
and reached a diameter of over 220 p. 
