POLYCARPIC^:. 379 



either a nut or a follicle (Act&a has berries). The seed has a large, 

 oil-containing endosperm and a small embryo (Fig. 374). 



The main axis generally terminates in a flower, and the lateral axes branch 

 in a cyrnose manner (Fig. 371). The flowers show the following differences in 

 constiuction: VEBTICILLATE (EUCYCLIC), i.e. constructed all through of alt mating 

 whorls: Aqiiiletjia (Fig. 370), Xanthorhiza, and sometimes Erantliis. SEMI- 

 YERTICILLATE (HEMicYCi.ic) /.c. with sepals and petals in alternate whorls, and 

 the others arranged spirally: Ranunculus (Fig. 371), Mi/osiirus, Pteonia and 

 several other genera entirely, or in certain species only. SPIRAL-FLOWERED 

 (ACYCLIC) i.e. all the leaves are arranged spirally, so that sepals and petals do 

 not alternate the one with the other, even though they are the same in number : 

 Adonis (Fig. 372), Aconitinn, Delphinium-species, Nigella -species, Hellcborus. 

 The leaves of the calyx are in this instance arranged on a spiral of | ; those of 

 the corolla on f, f, ^ or 2 R T , and stamens and carpels likewise on higher 

 fractions of the same series. 



The genera Caltlia, Anemone, TJialictrum and Clematis have a single perianth, 

 which is most frequently petaloid ; it is thus apparent that the sepals are 

 petaloid, and the leaves, which in other genera have developed as petals, are in 

 these instances stamens. The calyx is similarly petaloid in the genera Hclleborus, 

 Erantliis, Nigella, Delphinium and Aconitum ; but the petals are present in these 

 instances in unusual (horn-like) forms, and almost entirely given up to the 

 function of nectaries, a function they already possess in Ranunculus. According 

 to a more recent theory the " honey -leaves " are transformed stamens, which 

 have lost the function of reproduction ; the perianth is then single, and most 

 frequently petaloid. [Those leaves in the flowers of many Ranunculac^ffi 

 which bear nectaries are termed by Prantl honey-leaves, and comprise those 

 leaf-structures of the flower whose essential function lies in the production 

 <>f nectar, and which, independent of the differentiation of the perianth into 

 calyx and corolla, are derived from the stamens by the loss of their reproductive 

 functions. Clear transitional forms are found between the two series of the 

 perianth (^.17. between the sepaloid and petaloid perianth-leaves of Anemone 

 japonica, A. decapetalu, Troll 'ms-species) while transitional forms are never 

 found between perianth- and honey-leaves (with the exception of Aquilenia 

 vulgaru, var. stellata). In Anemone and Clematis the honey-leaves pass 

 gradually into the stamens, and agree with the stamens in the other Rauuu- 

 culaceae in their arrangement, development, and scant system of veins (except 

 Nigella). In Delphinium, sect. Consolida, the two honey-leaves placed in front 

 of the unpaired perianth-leaf are united into one, as shown by the veins (twice 

 three veins arranged symmetrically). The honey-leaves of A quite a ia, Calliun- 

 tliemnm, and the majority of the Ranunculus-species serve by reason of their 

 large circumference, as organs of attraction, and on this account are considered 

 as petals by other authors. The same position in the flower which the 

 honey-leaves assume is found occupied by staminodes, without nectar, in some 

 C >ptis-species, in Anemono2)sis, Acttca sect. Euactica, {e.g. A. racemosa), Clematis 

 sect. Atrageue; in the last-named they closely surround the stamens, in Actcc.a, 

 they are petaloid. A perianth, sharply differentiated into calyx and corolla, 

 and destitute of honey-leaves, is found in Anemone, sect. Knoirltonia (Cape), 



