166 LAMPROTHAMNUS ALOPECUROIDES. 



globule, which is supposed to represent the male organ, and the 

 nucule the female. Their relative position to each other differs in 

 each genus. In the Chora the globule is placed below the nucule ; 

 in Lamprotliamnus the globule and nucule repose side by side; while 

 in Lychnothamnus, which is dioecious, they are on separate plants. 

 In Tolypella, which is monoecious, the globule lies at the forkings of 

 the branchlets, and is surrounded by nucules more or less numerous. 

 In Nitella the globule rests above the nucule in the forkings of the 

 branchlets of the plants which are not monoecious. The Characece 

 are reproduced both sexually and asexually. In the former case 

 the organs of reproduction do not correspond with those of 

 Thallophyllce, Muscinece, or vascular Cryptogams. The nucule of 

 Char a vulgaris, which may be taken as an example of the group 

 consists of a seed-vessel, enclosed in a membranous brittle envelope, 

 around which are five spiral cells, surmounted by five smaller ones ; 

 these cells pass from right to left, in a direction the reverse of the 

 stem and branchlet-cells, and contrary to their course of circulation. 

 Each seed-vessel contains only a single germ ; when young it is of a 

 green colour, but when mature becomes darker, and connected only 

 by its brittle envelope ; when disengaged it shows a dark shining 

 body. The structure of the globule is more complicated ; it is green 

 in fruit, and turns to red or orange when mature, which is princi- 

 pally owing to the small red granules it contains. The asexual 

 reproduction of this family is effected by three methods : the most 

 general is by bulbils, situate at the basal node of the rootlets ; 

 the reproduction by the two other methods is by spores 

 which spring from the base of the verticillate branch, and do not 

 require any special notice. The stem of the Chara is usually 

 striated or furrowed, more or less hispid, and very fragile after 

 dessication. The internodes consist of a central tube, covered 

 with a series of smaller tubes, which entirely envelope them. The 

 whorls of the branchlets have a series of involucral papillae at their 

 union with the stem. The stem of Nitella is smooth and 

 flexible when dry ; the whorls have no involucral papillse at their 

 base, and the branchlets are forked at the summit. This section of 



