RANALES 405 



Illiciaceae 



lllicium, a genus of shrubs and trees, with bisexual flowers, many 

 tepals, stamens, and carpels, has been variously placed taxonomically 

 within the Ranales. It is considered to form the family Illiciaceae, with 

 closest resemblance to the Schisandraceae. 



The floral structure is primitive; the numerous organs are free and 

 spirally placed, except the carpels, which are whorled. The nodes are 

 unilacunar, with a single strong trace. The wood and phloem show a 

 combination of primitive and advanced characters. The vessel members 

 are long and slender, with long-overlapping ends, which have manv 

 scalariform perforations. The tracheary pitting ranges from scalariform 

 to opposite-multiseriate. The sieve elements are like the vessel mem- 

 bers in shape imd have numerous sieve areas. There are no fibers in 

 the secondary phloem. 



The Illiciaceae resemble the Schisandraceae more closely than other 

 ranalian families. 



Calycanthaceae 



The family Calycanthaceae consists of two small genera of shrubs, 

 Calycanthus and Chimonanthus. 



The flowers have a concave receptacle with numerous petaloid tepals 

 borne spirally on its sides and few to many stamens, sometimes with 

 staminodes above the stamens. The manv carpels are borne, also in 

 spirals, on the sides and at the bottom of the concave receptacle. There 

 is no distinction of calyx and corolla. The stamens have a short fila- 

 ment and large anther, with broad and prolonged connective and elon- 

 gate, laterodorsal anther sacs. The pollen is dicolpate. The carpels are 

 achenelike, with a long filamentous style and a decurrent stigma, re- 

 sembling that of CercidiphyUum. The ovules are one or two. The 

 archesporium consists of eight to ten cells. The embryo is large, and 

 there is no endosperm. 



Pollination is largely or wholly by beetles. The inner tepals, like 

 those in Eupomatia, bend inward, forming an imbricate roof over a 

 chamber in which pollination takes place. The tips of some of these 

 tepals and the prolonged connectives of the stamens bear food bodies 

 (Fig. 69). In some species, the stamen tips are conspicuous — white, 

 on the dark red stamen, and lack the hairy coat of the anther; they 

 are, perhaps, associated with pollination. The food bodies consist of 

 delicate cells, rich in protoplasm and oil. There are no nectaries; nectar 

 is secreted by the inner staminodia, and fragrant oils probably diffuse 

 from the perianth, as in Magnolia. 



The wood has simply porous vessels and paratracheal parenchyma; 

 the phloem has sieve cells, with single, transverse end plates. These are 



