CHARA DENUDATA. 41 



6-8 branciilets. Stipulodes of both serieKS short, ovoid. 

 Branchlets spreading or somewhat incurved, of 4-6 seg- 

 ments, the lower 2-3 often long, the upper 2-3 usually 

 short ; cortex rudimentary, represented by a ring of 

 cells at each fruiting node, one anterior cell often 

 lengthening and projecting below the antheridium. 

 Bract-cells normally 5, obtuse or subacute, the anterior 

 pair much shorter than the fruit, the rest rudimentary 

 or the second pair occasionally elongated ; hracteoles 

 about equalling the fruit. Oogonia and antheridia 

 solitary or geminate, produced at the lowest 2-3 branch- 

 let-nodes. Oogonium c. 1000-1100 y. long (excl. cor.), 

 c. 550-600 [X broad ; spiral-cells showing 13-15 con- 

 volutions ; coronula c. 175-200 ii high, 350-400 (x broad, 

 spreading. Oospore varying considerably in shape and 

 size, obovoid, ellipsoid or cylindrical, c. 675-825 fx long, 

 400-450 [X broad, reddish-brown to nearly black, showing 

 12-14 fine well-marked ridges terminating in basal 

 claws ; outer membrane thick, semi-rigid, translucent, 

 red-brown, very finely granulated. Antheridium 400- 

 425 [X in diameter. 



Habitat and Distribution. — Ireland : In Brittas 

 Lough, a small deep lake near Mullingar, Westmeath, 

 occurring in about 12 feet of water. Discovered by the 

 late Mr. H. C. Levinge in 1892. Not at present known 

 from any other locality in the British Isles, but should 

 be looked for in other deep lakes. 



First record : ' Journ. Bot.,' 1895. 



Outside the British Isles C. denudata is recorded from 

 Switzerland, Lac de Neuchatel in 60 feet of water, and 

 Italy, Lago di Mantua, as well as from Cape Colony, 

 Strombergen, at an elevation of 5000-6000 ft. (Drege). 



A medium-sized weak drawn-out straggling grey-green plant 

 with rather slender stem and branchlets, the habit being no doubt 

 due mainly to the conditions of growth, considerably incrusted. 

 Evidently closely related to C. contraria, of which it should 

 probably be regarded as a subspecies, or possibly only a series 

 of degraded states. It is distinguished principally by the 



