LAMPROTHAMNIUM PAPULOSUM. 9 



First record : Babington, 1863. 



Outside the British Isles L. papillosum occurs in 

 Norway, Sweden, Denmark, Northern Germany (Baltic 

 Coast), Spain, France, Italy, N.W. Africa (Algiers) and 

 S. Africa (Port Elizabeth). 



Extremely variable in stature, but usually a small or medium- 

 sized plant. In France, where it is widely distributed, Prof. Hy 

 states that it ranges in height from 3 to 40 cm. The English 

 forms are mthout incrustation. 



It is remarkably distinct in facies from any other British 

 Charophyte ; the long fox-tail-like heads, from which the 

 happily chosen specific name alopecuroides was taken, and the 

 long slender graceful stipulodes, attaining to a length of about 

 3 mm. and conspicuously spreading downwards, serve to dis- 

 tinguish it at once in the field. An important characteristic is 

 the production of simple whitish usually spherical root-bulbils, 

 attaining a diameter of about 1 mm., and occurring in clusters. 

 Miss Mary McNicol, Annals of Botany XXI, pp. 61-70, t. 8 

 (1907), has given a careful account with illustrations of the 

 structure and development of the bulbils and pro-embryo of the 

 South African plant, an extremely vigorous form, the branch- 

 lets often exceeding ten in number and a circle of stipulodes 

 produced above as well as below the branchlets. Miss McNicol 

 finds, in the terminal process of the pro-embryo, that the 

 middle of the three cells of which it is composed is often so 

 much swollen as to be almost spherical. In Dr. Giesenhagen's 

 valuable paper (I.e.), the structure of the stem- and branchlet- 

 nodes is fully described and figured. The terminal segments of 

 the branchlets, the bract-cells and the stipulodes have often long 

 hyaline tips owing to a thickening of the cell-wall. The bract- 

 cells are occasionally short and stout with mucronate tips. 

 Minute accessory bract-cells are sometimes developed. 



The oogonia with hme-shell, which are very numerous in this 

 species, exhibit a peculiar feature, not, as far as we know, observ- 

 able in any other Charophyte. The spiral-cells at the point 

 where they near the apex and close in to form the neck cease to 

 secrete lime, with the result that the deposit stops short at this 

 point, leaving the lime-shell with a truncated top (see fig. 9), 

 out of which the oospore protrudes. 



The British examples present a wide range of variation of 

 form, from a robust broad-headed state, such as that from the 



