428 GENERAL REVIEW. 



known in Continental gradens as P. hybridum meldense ; and 

 the union of P, bracteatum and P. somniferum has produced a 

 race of showy garden plants. The hybrid between P. orientate 

 and P. somniferum was known to Linnaeus; and the fact is 

 noted in the ' Journal de Physique,' t. xxxii., p. 459 : "I have 

 seen in the Botanic Garden, Edinburgh, a hybrid plant pro- 

 duced by the Oriental Poppy and the Opium Poppy. The 

 stamens were removed from the flowers of P. somniferum just 

 before they expanded, the stamens of P. orientate being placed 

 on the stigmas after they became well developed. This experi- 

 ment was repeated several years with equal success." 



THE PEA FAMILY (Papilionacea). 



A large group of plants, for the most part readily recognised 

 by their irregular Pea-like flowers, while some of the species are 

 among the most nutritious of all our food-plants. The prin- 

 cipal genera in our gardens are Baptisia, Brachysema, Gom- 

 pholobium, Hovea, Goodia, Lupinus, Ulex (Furze), Spartium 

 (Broom), Genista, Laburnum, Trifolium (Clovers), Ononis 

 (Rest-harrow), Indigo/era (Indigo), Glycyrrhiza (Liquorice), 

 Wistaria, Robinia, Clianthus (Glory Pea) Colutea, Pisum 

 (Peas), Ervum (Lentils), Lathyrus (Sweet-peas), Orobus, Ara- 

 chis (Pea-nuts), Coronilla, Desmodium, Hedysarum, Erythrina, 

 Phaseolus (Scarlet -runner), Dolichos, Abrus (Crabs' - eyes), 

 Sophara, Virgilia, Cassia, Brownea, Amherstia, Jonesia, Bau- 

 hinia, Cercis, Acacia, Fab a (Beans), and others. They are 

 distributed over nearly every part of the earth's surface, many 

 being annuals, while the Acacias, Robinias, and others, are 

 large trees; many others being either herbaceous plants, as 

 Lupins, or scandent undershrubs, as Kennedya and Harden- 

 bergia. As a rule, all the species produce fertile seeds freely, 

 and in most cases these germinate if sown as soon as ripe in 

 autumn, or in the following spring. The herbaceous peren- 

 nials are easily increased by seeds or division ; and most of 

 the shrubby kinds are propagated successfully from cuttings 

 inserted in heat, or by layers. Grafting is employed for the 

 numerous beautiful varieties of the Robinia, the stocks used 

 being seedling plants of R. pseud-acacia. 



There is a great deal of variation in the structure, arrange- 

 ment, and curvature of the stamens of papilionaceous or Pea- 

 flowered plants; and this variability seems, in the majority of 

 cases, to favour cross-fertilisation by insect agency. In Cassia 

 we have two very long stamens, while the rest are much 

 shorter, and curved, or set at different angles. In Amherstia 



