Germination and Growth of Species of Salvia. 359 



the cotyledons is uppermost ; they are perhaps three times 

 as long and three times as broad as they were when 

 enclosed within the seed. Thus the actual measurements of 

 S. Forskohlci, when first noticed above the soil, were 3 mm. x 

 3 mm. ; nor were there other species noticed that differed 

 much from these dimensions, S. interrupta, the largest of 

 the nutlets, having perhaps dimensions 4 m. x 4 m. 



All the species were characterised by thick, almost fleshy, 

 cotyledons, which remain appressed only for one or two 

 days, as a rule, after emergence through the soil ; in all the 

 colour is light, and they are generally smooth, in only a very 

 few instances appearing pubescent on the upper or under 

 surfaces. 



In the case of S. interrupta, which we must again notice, 

 on account of other peculiarities, the cotyledons remained 

 appressed for a number of days. Commonly, in favourable 

 circumstances, the cotyledons spread their upper surfaces to 

 the light quickly, after which a considerable increase in 

 size and shape, and ultimately the development of petioles, 

 may be noticed. 



The ordinary phenomena of the growth to be observed in 

 these species of Salvia are as follows : — 



After the cotyledons are no longer in contact with their 

 upper surfaces, they lie at first inclined to one another, 

 subsequently in the same plane, or again inclined according 

 to their position with regard to the amount of light to which 

 they are exposed. They are commonly symmetrically opposed 

 the one to the other ; but in exceptional circumstances one 

 may grow nearer to the other, if thereby it gains advantage 

 from a better exposure to light. This ability in the cotyledon 

 to place itself so that it is exposed to a greater amount of 

 light is dependent mostly upon the growth of the cells in 

 the petioles, but also in some species upon gi-owth or 

 variation in the turgescence of cells situate about the point 

 of union of petiole and lamina ; alteration at this point 

 allows the lamina to lie in the same plane as the petiole, or 

 to be at a greater or less angle to it. This variation in the 

 inclination of the lamina, as distinct from the petiole, was 

 noticeable most distinctly in those species where there is an 

 abrupt transition from petiole to lamina. 



The maximum increase in the size of the lamina occurs 



