5 8 ASCLEPIADA CEA E 



or Hanes, with simple, entire, opp., exstip. 1. Latex is present. Many, 

 esp. S. Afr. sp., xero. ; some, e.g. Periploca, with much reduced 1., 

 others, e.g. Hoya. and still more, Stapelia, with fleshy stems. Epiphytes 

 also occur ; cf. esp. Dischidia. 



Infl. usu. of many fls. and cymose or racemose (raceme or umbel). 

 In the former case it is dich., but as in Caryophyll. the one branch 

 tends to outgrow the other, and a monoch. (cincinnus) may arise in 

 later branchings. When infl. axillary, there is usu. only one at each 

 node; in the axil of the other 1. there is a veg. shoot, or nothing. 

 In some gen. (cf. Asclepias) the infl. is extra-axillary. 



Fl. 5, reg , j-merous, usu. small. K 5, quincuncial, the odd sep. 

 post.; C(5) usu. rotate or campanulate, with conv. or valvate aesti- 

 vation. The essential organs (5 sta., 2 cpls. ) are complex. The sta. 

 and style are usu. united to form a gynosteginm. The cpls. are free 

 below as in Apocyn., but united at the tip with a common style ; ov. 

 sup. The head of the- style is large and variously shaped, and the 

 stigmatic surface is usually upon the edge or under side of it. To its 

 margin are united the anthers of the 5 epipet. sta. ; the filaments of 

 these are short or non-existent. The pollen in i is united merely 

 in tetrads, in the higher group, comprising the bulk of the order, into 

 pollinia, as in Orchids. Usu. each anther contains two. In this 

 group also there are curtain-like projections at the sides of the anthers, 

 leaving a narrow slit between each pair of anthers. 



The pollen is removed from the anthers by a curious mechanism 

 the translator. This differs in the two suborders and so also does the 

 fert. method. The translator always stands between two anthers 

 and serves to carry away half the pollen from each of them. In the 

 Periplocoideae it is a spoon- or funnel-like body with a sticky disc at 

 the narrow end. Into it is shed the pollen from the two half anthers 

 next to it, and as the sticky disc projects outwards in the male stage 

 of the flower an insect will be likely to get it attached to its head, 

 and carry it about like the pollinia of an orchid. In visiting a second 

 flower the pollen may be placed on the stigmalic surface. In the 

 Cynanchou/eae, on the other hand, there are pollinia, and the trans- 

 lator has a different structure. It forms an inverted \-shaped organ, 

 the foot of the Y being formed by the adhesive body (corpiisculuni] ; 

 from this diverge the threads (retinaculn) which are attached to the 

 pollinia, one in each anther. An insect in obtaining honey catches 

 its leg in the slit between the anthers, and in drawing it up removes 

 the pair of pollinia. The threads as they dry contract on the inner 

 side till the pollinia meet, thus closely clasping the insect's leg. In 

 drawing the leg through a similar slit in another fl. the pollinia catch 

 on the stigmatic under-surface of the stylar head. (Cf. Apocynmn, 

 which shows an approach to this mech.) 



The backs of the anthers as a rule bear appendages (ciiculli) 

 forming a corona. In some cases it springs from the C. It may 

 consist of small teeth, or be more complex, as in Asclepias and 

 Ceropegia, and often takes up the functions of secreting and storing 

 the honey. 



G (2), -z-loc., with oo anatr. ov. pend. from the ventral plac. Fr. 

 a pair of follicles; seeds usu. crowned by a tuft of hairs for wind- 



