100 Mr. Brown's Olmcrvatioiis on the 



and according to this view the order of expansion is direct, the 

 central female flower being the representative of the terminal 

 partial spike. 



There is even a third species of inflorescence with which the 

 fasciculus of Euphorbia may be compared, namely, that consist- 

 ing of one or more verticilli with a single flower in the centre. 

 In this, which may be considered a modification of the spike 

 or umbel, the usual order of expansion seems to be from centre to 

 circumference. Its simplest form occurs in an unpublished New 

 Holland genus of the same natural family with Euphorbia, in 

 which a single verticillus of male flowers surrounds the central 

 female flower. Lambertia may be considered as another instance of 

 the same mode, and as far as can be determined, in a case where 

 the flowers are hermaphrodite and their expansion nearly synchro- 

 nous, following the same order. In all the known species of this 

 genus the leaves are verticillate, and uniformly in threes : in 

 L.formosa and inermis the involucrum constantly contains seven 

 flowers, while in L. uniflora it is reduced to one flower. The sevea 

 flowers of the two former species I consider as made up of two 

 verticilli, in number of flowers corresponding with that of the 

 leaves, and of a single central or terminal flower; to which termi- 

 nal flower L. uuijlora appears to be reduced. From this order of 

 reduction it may be assumed as more probable that species of 

 Lambertia should be found with ten or four flowers in the involu- 

 crum than with nine, six, or three. But greater permanence being, 

 as has been already remarked, generally connected with greater 

 perfection, it becomes also probable that, if any species of this 

 genus should be discovered with androgynous capitula, the female 

 flower will occupy the centre as in the genus of Euphorbiaceae 

 above referred to. 



It is worthy of remark, and may indeed appear in some degree 



at 



