26 



PRACTICAL PLANT PROPAGATION 



years if kept dry and cool. Some seeds are peculiar in that they 

 sometimes develop only the cotyledons and the roots the first 

 season. One or two species of Ipomoea have this peculiarity. 



"A well known instance of this nature also occurs in one or 

 more of the common Oaks. The seeds of the Coffee plant develop 

 cotyledons which sometimes remain in this condition for several 

 months before true leaves are developed." 



Three Cassia seeds are known to have germinated when 85 

 years old. It is doubtful whether the wheat seed found several 

 years ago in the pyramids of Egypt were as old as was claimed, 

 and if so, it is hardly to be believed that they grew. 



LONGEVITY, IN YEARS, OF FLOWER SEEDS 



(Derived mainly from data furnished by H. A. Dreer, Inc.) 



Abutilon 3-4 



Achillea 2 



Acroclinium 2-3 



Ageratum 2-3 



Agrostemma 3-4 



Agrostis nebulosa.2-3 



Alyssum 2-3 



Amarantus 3-4 



Ampelopsis 1 



Anchusa 2 



Anemone 2 



Antirrhinum 3-4 



Aquilegia 2 



Arabis 2-3 



Armeria 2 



Asters, China. . ..2-3 



perennial 1-2 



Auricula 2 



Balloon Vine 3-4 



Balsam 6-8 



Baptisia 3-4 



Begonia 2 



Bellis 2-3 



Bocconia 1 



Brachycome 3 



Briza maxima 2-3 



Browallia 2-3 



Cacalia 2 



Calceolaria 2-3 



Calendula 3-4 



Calliopsis 2-3 



Campanula 2-3 



Canary Bird Vine. 3-4 



Candytuft 2-3 



Canna. ., ..3-4 



Carnation 3-4 



Cassia 2-3 



Celosia 4-5 



Centaurea 2 



Gerastium 2 



Chrysanthemum. . 3-4 



Cineraria 3-4 



Clarkia 2-3 



Clematis panicu- 



lata 1 



Gleome 2-3 



Cobaea 1-2 



Coix 2-3 



Coleus 2 



Convolvulus 3-4 



Coreopsis 2 



Cosmos 2-3 



Cyclamen 2 



Cypress Vine 3-4 



Cyperus. 1 



Dahlia 2 



Datura 3-4 



Delphinium 2 



Dianthus 3-4 



Digitalis 2 



Dimorphotheca . . 2 



Dolichos 3-4 



Dracaena 1 



Echinocystis 4-5 



Echinops 2 



Eryngium 2-3 



Erysimum 3-4 



Eschscholtzia . ... 2 



Eupatorium 2 



Euphorbia 3-4 



Ferns 3-4 



Gaillardia 2 



Gaura. 2-3 



Geranium 3 



Geum 2 



Globe Amaranth . 2-3 



Gloxinia 2-3 



Godetia 2-3 



Gomphrena 2-3 



Gourds 5-6 



Grevillea 1 



Gynerium 2-3 



Gypsophila 2 



Helenium 3-4 



Helianthus 2-4 



Helichrysum 2-3 



Heliopsis 2-3 



Heliotrope 1 



Hibiscus 3-4 



Hollyhock 4-5 



Humulus 1 



Hunnemannia 2 



Iberis 2-3 



Impatiens 5-6 



Ipomoea 3-4 



Iris 2 



Kochia 2 



Lantana 1 



Larkspur Annual 



3-4 

 Lathyrus latifolius 



3-4 



Lavandula 2 



Lavatera 3-4 



Liatris. .. 2 



