60 



BASES AND CRITERIA. 



community. This capacity is due in some cases to the prolific production of 

 seed, but usually to more vigorous vegetative multiplication by means of 

 traveling shoots, or shoots given off from the root. And this latter is to some 

 extent determined by the soil (moist or wet soil, loose sandy soil, etc.) " 



Warming divides growth-forms into six classes and subdivides this into 

 subclasses and types as follows: 



1. Heterotrophic growth-forms: holopara- 



sites and holosaprophytes. 



2. Aquatic growth-forms. 



3. Muscoid growth-forms. 



4. Lichenoid growth-forms. 



5. Lianoid growth-forms. 



6. All other autonomous land-plants. 



I. Monocarpic herbs. 



(a). Aestival annual plants. 

 (6). Hibernal annual plants, 

 (c). Biennial-perennial herbs. 



II. Polycarpic plants, 

 (a) Renascent herbs. 



(1) Herbs with multicipital rhizomes: 



Silene inflata. 



(2) Mat-geophytes. 



a. With stem-tubers: Crocus. 



b. With root-tubers: Ophrydeae. 



c. With bulbs: Liliaceae. 



' d. With perennial tuberous stem: 



Cyclamen. 



(3) Rhizome-geophytes. 



a. On loose soil of dunes: Ammo- 



phila, Carex. 



b. On loose humus soil in forests: 



Polygonatum, Anemone nemo 

 rosa. 



c. On mud in water or swamp: 



Phragmites, Hippuris. 

 (6) Rosette-plants. 



(1) Leaves sessile, elongated: Plan- 



tago, Taraxacum. 



(2) Leaves long-stalked, broad: Ane- 



mone, Hepatica. 



(3) Leaves succulent: Crassulaceae. 



(4) With runners: Fragaria, Poten- 



tilla anserina. 



(5) Flowers on leafy shoots: Alche- 



milla, Geum. 



(6) Flowers on leafless shoots: 



Primula. 



(8) 

 (9) 



6. All other autonomous land-plants — cont. 

 II. Polycarpic plants — continued, 

 {b) Rosette-plants — continued. 



(7) Grass-rosettes: grasses, sedges, 

 Eriocaulaceae. 

 Musa-f orm : gigantic tropical 



herbs (banana). 

 Tuft-trees. 



1. Trunks without second- 

 ary growth; leaves large and 

 divided: tree-ferns, palms, 

 cycads. 



2 . Trunks with secondary growth ; 

 leaves undivided, linear; 

 Yucca, Dracaena. 



3. Strelitzia-form. 



(c) Creeping plants. 



(1) Herbs: Lycopodium clavatum, 

 Menyanthes. 



(2) Dwarf shrubs: Arctostaphylus 

 uva-ursi, Linnaea. 



(3) Jungermannia-form. 



(d) Land-plants with long, erect, long- 

 lived shoots. 



(1) Cushion-plants: Silene acaulis, 

 Azorella. 

 Undershrubs : 



(2) 



1. Labiate type: Salvia, Thymus, 



Artemisia. 



2. Acanthus type: Acanthaceae. 



3. Rhizome-undershrubs: Vac- 



cinium myrtillus. 



4. Cane-undershrubs : Rubus 



idaeus. 



5. Soft-stemmed plants: Araceae. 



6. Cactus-form: Cactaceae, Sta- 



pelia. 



7. Woody plants with long-lived 



lignified stems, canopy-trees, 

 shrubs, dwarf shrubs. 



Drude, 1913.— In broadening his earlier classification into a universal 

 system of life-forms, Drude (1913 : 29) has applied the following criteria: 



1. The basic form (tree, shrub, annual or perennial herb), by the organization of which for 



a long period of vears, or for a single season of growth, each plant maintains its 

 own place. The'method of propagation is an essential part of this basic form. 



2. The form and duration of the leaves. 



3. The protective devices of leaf- and flower-shoots during the period of rest. 



4. Position and structure of the organs of absorption. 



5. Flowering and fruiting in relation to reproduction as a single or recurrent process. 



