HARDWICKE'S SCIENCE-GOSSIP. 



121 



A PLEA FOR OUR CHARAS. 



By JAMES SAUNDERS. 



£f HAT this curious 

 group of aquatic 

 plants has received 

 but little attention 

 from British bota- 

 nists, is generally 

 admitted, but that 

 period of indif- 

 ference is appa- 

 rently passing 

 away. For several 

 years past a few 

 enthusiastic but 

 comparatively iso- 

 lated workers have 

 investigated vari- 

 ous parts of the 

 country, with gra- 

 tifying success. 

 Much, however, 

 remains to be 

 done. For many counties and vice-counties there are 

 either no records or but unreliable ones ; and it is 

 with the earnest desire that, by directing attention 

 to these facts in the pages of Science-Gossip, some 

 of its numerous botanical readers will be stimulated 

 to/work up those of their own localities, if not hitherto 

 attempted. By such means the British census of these 

 plants which is now in progress by the Messrs. Groves, 

 will more speedily be sufficiently complete to warrant 

 its publication. 



As, however, many of the readers of Science- 

 Gossip may not have observed any growing Charas, 

 as was confessedly the case with the writer till late 

 in the autumn of 1881, although he had searched 

 unsuccessfully for two years, a few hints as to their 

 habits may be acceptable. Now, the only wonder is, 

 how they could have been overlooked so long. 

 Where, then, should they be sought ? In ponds, pools, 

 and ditches chiefly, and also in running water, but 

 in this they occur more rarely. There are however 

 certain ponds in which it would be useless to seek 

 them, as, for example, those that are frequented by 

 No. 222. — June 1883. 



domestic ducks, as these useful creatures devour the 

 aquatic vegetation. It is equally useless to search for 

 them in shaded pools, or on the shady side of them ; 

 for, so far as the limited experience of the writer has 

 gone, they appear to grow only in such situations as 

 are fully exposed to direct sunlight. In confirmation of 

 this, it may be mentioned that a flexible species ( Toly- 

 pella intricata) now growing in a glass jar, in a window 

 facing south, invariably has its growing branches 

 raised near to the surface of the water during sunny 

 days, and they sink near to the bottom during dull 

 days. This is suggestive that the action of direct 

 sunlight is a great stimulus to their growth, and is 

 probably essential to their existence. 



As to the time for Chara hunting, it might be said, 

 Look for them all through the year, both in season 

 and out of season, although it will be easily under- 

 stood that in the summer months they are in best 

 condition, and their curious fruits are ripe. It 

 was very late in the autumn of 1881 that the writer 

 first observed any of them growing. The true 

 flowering plants were all gone ; the chill autumn 

 winds rustled mournfully through the dry rushes 

 and sedges along the margin of a rivulet ; regrets 

 that the work for another^season was over reigned 

 paramount, when the eye was arrested by a dark 

 green patch, of an unfamiliar appearance. In some 

 respects it resembled an aquatic Crow-foot ; in 

 others, it was dissimilar. A hooked stick was quickly 

 brought into requisition : some of the plant was 

 drawn up, and speedily recognised as being one of 

 the long-sought Characere. It afterwards proved 

 to be Nitella opaca, one of our most frequent species. 

 Since that time, one has been enabled to detect them 

 in many localities in South Beds, especially in quiet 

 pools, remote from the haunts of men. In some 

 instances they grow so vigorously as to exclude most 

 other forms of vegetation, but this is not of frequent 

 occurrence. As an encouragement to those who 

 might be stimulated to take up the subject, it may 

 be mentioned that two of our rarest British forms* 



* They are Nitella mucronata and Tolypella intricata. For 

 the former see '* Journal of Botany " for Jan. 1S83. 



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