1902 Maj'sh Botany in Winter 57 



dews are starred all over the moss which grows over the 

 peat, I found a dyke almost choked with water - soldiers 

 (Stratiotes aloides). The water-soldier, which, as its scientific 

 name implies, is not unlike an aloe in appearance, is a 

 characteristic fen-plant, fairly plentiful in our marsh dykes 

 and shallow broads. It is one of the most interesting 

 of the genuine Hydrophytes — i.e., water plants — which, 

 unlike some of the duckweeds and water-crowfoots, cannot 

 exist for any length of time out of water. All through the 

 winter it lies at the bottom of the dykes, to all appearances 

 as dead as its neighbouring sedges and water-plantains ; but 

 when spring comes it rises to the surface, produces fresh 

 leaves, and subsequently flowers resembling those of the 

 frog-bit. When it has done flowering it sinks again ; but 

 towards the end of summer, when the buds are produced, 

 it rises a second time and floats until the shoots which 

 connect the young plants with it have rotted, when the 

 latter become detached and, with the parent plant, sink 

 to the bottom and remain there through the winter. So 

 the water- soldier may be said to hibernate, as do those 

 strange insectivorous water-plants the bladderworts {Utri- 

 cularia). To some extent this remark applies to the duck- 

 weed ; but it is not correct, as is often stated, that at the 

 approach of winter all the duckweeds sink to the bottom 

 of ponds and ditches over whose surface they have spread a 

 "green mantle" during the summer months. In the course 

 of my ramble I found the surface of several dykes coated 

 with these minute plants. On investigation they proved to 

 be Lenina minor and L. polyrrhiza, perhaps our commonest 

 species. The ivy -leaved duckweed (Z. trisulca), however, 

 which is almost equally common in the marsh dykes, nearly 

 everywhere had sunk to the bottom. The duckweeds are 

 plants which almost every one would say are wholly am- 

 phibious ; but those of our British species which have roots 

 — that is to say, all of them except L. arrhiza — are capable 

 of maintaining themselves, at least for a time, should the 

 pond or ditch in which they grow " dry up." Their slender 

 hair-like roots, which usually absorb nutriment from the 

 water, attach themselves to the mud, from which they 

 obtain food-stuffs until the pond or ditch fills with water 



Iff 



