HALORAGE^ 117 



Two species of Water-Milfoil — M. verticillatum, L., 

 with the floral leaves all pinnatifid or pectinate, longer 

 than the flowers ; and spicatuni, L., with the upper leaves 

 entire, shorter than the flowers, occur in Switzerland ; 

 and the third British species, M. alterniflorumy DC, also 

 in the Vosges and Pyrenees. 



3. Callitriche, L. 



Flowers minute, solitary, axillary, unisexual; perianth 

 o ; stamen i ; styles 2 ; leaves opposite, entire. Water- 

 plants. 



C. vernUy L., Water -Starwort, with numerous sub- 

 species ; common in ponds and streams. 



Order XXXIV.— LYTHRACE^. 



Petals 3-6 or o ; calyx tubular, enclosing the ovary ; 

 stamens inserted on the calyx-tube ; ovary 2-6-celled ; 

 leaves always entire, opposite or in whorls. A mode- 

 rately large order, chiefly tropical ; not alpine. 



I. Lythrum, L. 



Flowers axillary, usually bisexual ; petals 4-6, red or 

 pink; stamens 8-12; seed-vessel a 1-2-celled capsule. 



L. Salicariay L., Purple Loosestrife; flowers large, 

 purple, in axillary whorls ; stamens and styles of three 

 different lengths ; leaves often in whorls of 3 ; wet places, 

 common. L. Hyssopifolia^ L. ; flowers solitary, small, 

 pink, leaves usually alternate ; wet places, rare. 



