56 BRITISH CHABOPHYTA. 



Ireland : Tipperary, S., Limerick, Tipperary, N., 

 Kilkenny, Queen's Co., Galway, S.E., W. & N.E., 

 King's Co., Kildare, Dublin, Meath, Westmeath, Long- 

 ford, Eoscommon, Mayo, E. & W., Sligo, Leitrim, 

 Cavan, Monaghan, Fermanagh, Donegal, W., Down. 



First record : Groves, Mourn. Bot.,' 1898. 



Outside the British Isles we have seen specimens of 

 C. desmacantha from Sweden and Bavaria. 



A small to medium-sized plant, not usually exceeding a foot 

 in height, with rather stout rigid stem and branchlets. The 

 spine-cells, stipulodes and bract-cells are usually very well 

 developed, and the spine-cells being persistent and often in large 

 clusters, the plant is conspicuously spiny in appearance. The 

 spine-cells are often very long, sometimes as much as four times 

 as long as the diameter of the stem. The bractlet is as long or 

 almost as long as the bracteoles. 



The bulbils resemble those of Lamprothamnium paptihsum 

 and C. aspera, but we have not found them as frequently pro- 

 duced as in these species. 



C. desmacantha does not fruit freely and ripe oospores are 

 rarely foimd. This is perhaps hardly to be wondered at, con- 

 sidering its remarkably exuberant vegetative growth. We have 

 observed extra celk between the node-cells of the cortex and the 

 spine-cells, similar to those in C. aculeolata. 



It has a close superficial resemblance to C. canescens, for which 

 species it has been frequently mistaken even by the most 

 experienced collectors. An examination of the cortex will at 

 once disclose the sectional distinction between the two. It is 

 not so Ukely to be confused with the other very spiny species, 

 C. aculeolata, which besides being monoecious is, except in its 

 weakest states, larger and more robust, and has usually charac- 

 teristically upward-directed branchlets. The present species is 

 most nearly related to C. aspera, of which it has been regarded 

 as a subspecies or variety, but differs in the stouter and more 

 rigid stem and branchlets, and in the clustered persistent spine- 

 cells. The nodes of the cortex are more numerous than is usual 

 in C. aspera, there being 14-18 to an internode of the stem, 

 counting the opposite ascending and descending rows. 



The most typical forms are found in Ireland, where the plant 

 appears to have its headquarters. These have a stout rigid 

 stem, with moderately long straightish branchlets, often slightly 



