Grimes, Mimosoid legumes 
737 
Though the growth form superficially resembles that of Ebenopsis ebano (following) in 
that the species possesses stipular spines and axillary short-shoots, in growth pattern 
A. uilotica is more similar to Lysiloma microphyllum (Fig. 4); flowering occurs only on 
short-shoots, and these can develop sylleptically or proleptically. The RGU of the 
long-shoot is of a series of metamers, which are produced indefinitely in the greenhouse 
Fig. 4. Diagrammatic representation of the growth of Lysiloma microphyllum and Acacia nilotica. 
a, the repeating growth unit of non-blooming long-shoots; b & c, short-shoots. All flowers are 
produced on short-shoots, b, flowering from proleptically developing short-shoots only, 
independent of any long-shoots expansion; c, flowering on both proleptically and sylleptically 
developing short-shoots, the proleptic ones on the penultimate RGU. 
