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Occurrence of Potamogeton rufescens and P. prcelongus near 

 Kelvedon. By E. G. Varenne, Esq. 



The remark of the Rev. A. Bloxam in the last number (Phytol. 

 iii. 183), that " a botanist may almost every year be finding something 

 new in his neighbourhood," will be acknowledged to be true by most 

 of those who have followed the calling of field-botanist for any length 

 of time. It has often been my lot to wander by the banks of the 

 meandering Blackwater during the last ten or a dozen years, without 

 being able to discover any other Potamogeton than Potamogeton 

 lucens, growing in abundance in the stream. Circumstances lately 

 induced me to make a more accurate examination of our river pond- 

 weeds, and the result is that Potamogeton lucens is really uncommon 

 for about two miles of the course of the river as it surrounds the vil- 

 lage of Kelvedon. Its place is supplied by Potamogeton rufescens, 

 which presents itself in large masses in the bed of the river. Very 

 few floating leaves are formed under such circumstances, and the 

 flowers are elevated above the surface of the water without these ap- 

 pendages. My attention was first attracted to this circumstance by a 

 plant which I was fortunate enough to discover while in the company 

 of a fellow botanist, Mr. Bentall, in a pond near Mark's Hall, Cogges- 

 hall, in which there were as many stems in flower without floating 

 leaves as there were with them. The wingless stipules, equal peduncles, 

 and the form of the leaf, clearly distinguish this variety of rufescens 

 from Potamogeton lucens. In drying, whether furnished with floating 

 leaves or not, the peduncles, uppermost leaves, and stipules, assume a 

 purplish tint. 



There is also at the present time a fine bed of Potamogeton prae- 

 longus in full bearing in one situation, where it is surrounded by plan- 

 tations of Potamogeton rufescens. The long peduncles and branched 

 habit of Potamogeton praelongus, with the remarkable tips of its leaves, 

 and their unequal size, togther with the entire submersion of the plant, 

 are abundantly characteristic. 



E. G. Varenne. 



Kelvedon, July 11, 1848. 



