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THE PHYLLACTIDIUM PULCHELLUM. 



By E. D. Hakeop, F.R.M.S. 



Phyllactidmm Pulchellum ... Kutzing. Gray. 

 Coleocliaete Scutata Brebison. Hassall. 



It may be well to place on record tlie fact that this beautiful 

 microscopic plant has been noticed in Tasmania ; and as so 

 little is known of it even amongst microscopists, I will, at the 

 same time, with the permission of the Fellows of the Society, 

 describe it, and give a few lines on its history. 



The first occasion on which it was observed here was last 

 year by Mr. Sale, of Launceston, by whom it was found ad- 

 hering to the glass sides of his aquarium, and since then I 

 have discovered it in its natural habitat, namely, the leaves 

 and stems of water plants. I send prepared specimens for 

 examination by the Fellows. 



Although this plant was discovered in England in 1844 by 



Mr. Ralfs, who published a paper describing it in the " Annals 



of Natural History" in 1845 ; yet so seldom had it been 



noticed by Algologists, that Dr. Gray, F.R.S., described it in 



" Seeman's Journal of Botany," in 1866, as new to Great 



Britain. Kutzing appears to have been its first discoverer in 



1838, when he met with it growing in an aquarium. Brebison 



also observed it in 1844 at Falaise, growing on the leaves and 



stems of inundated and in part decomposed water plants, 



principally on the Sparganium natans and Potamogeton natans. 



He named it the Coleochaete Scutata, and from the setigerous 



sheaths, growing sometimes numerously from the upper portion 



of the cells, considered that it should be placed in the 



Chsetophoroidse, and near the Bulbochsete. The generic and 



specific names of Phyllactidium pulchellum first given it by 



Kutzing, and confirmed by Gray, are those by which it is now 



known. 



From the fact that this plant has generally been found 

 associated with, or rather in water in which the Volvox 

 Globator has been abundant, it was presumed by some ob- 

 servers that there was some connection between the plants ; 

 but its affinities are with quite another family of the Con- 

 fervoideae, namely, the Chsetophoracese. 



From most, if not all, of these plants there grows on the 

 back of some of the cells a sheath having a bulbous base, and 



