Character of the Genus Crj'ptolepis. 55 



stigmatic head is of a dilated and well-defined pentagonal form, vvithi an ab- 

 breviated conical apex. The margin is thinned off to rather a fine edge, which 

 at each of the five angles is notched with a sharp and rather deep emargina- 

 tion : the corners of these notches are tipt with a moist and viscid looking 

 denuded surface, differing in appearance and texture from the rest of the mar- 

 gin of the stigmatic head. Leading up from these emarginations to the apex 

 of the stigma, there are five straight, shallow, narrow, converging furrows, 

 along which are laid as many very delicate, narrow-oblong or linear, bronze- 

 coloured, horny-looking, transparent, membranous straps or appendiculse. 

 The lower end of these appendiculae is attenuated where it passes through the 

 marginal notch, and is applied to the centre of an oval, thin, delicate glandu- 

 lar corpuscle, which stretches across the notch, adhering to its under surface, 

 and placed in contact with the moist tips of its angles. They have no ad- 

 hesion at the fecundating stage with the furrows on which they lie, and are 

 readily detached, while the glandular corpuscle sticks with considerable tena- 

 city to the angles of the stigma. Pollen grains in irregular aggregations are 

 strewed interruptedly over the surface of the appendiculae, which is viscid. 

 Compared with the same organ in Cryptostegia, these appendiculae are ex- 

 tremely minute. 



I have examined a great number of flowers, with the object of finding some 

 of the pollen grains emitting their tubes at some point along the margin of 

 the stigma, with an instrument quite equal to the observation ; and tried in 

 some cases to excite the pollen artificially by applying it to the viscid corners 

 of the notches, but without success in either case. The extensive laceration 

 of the floral envelopes, and the rapid evaporation from the wounds during the 

 hot months in India, followed by very speedy withering, were at least suffi- 

 cient to account for the failure. 



Cryptolepis, although an unquestionable Periploceous Asclepiadea, appears 

 to constitute the closest known transition from that family to the Apocynefe, 

 in the very reduced state of evolution of the accessory stigmatic apparatus, as 

 compared with the other Periplocece ; in the lax aggregation of its pollen- 

 grains ; and in a portion at least of the stigmatic margin being in the ordi- 

 nary condition of a denuded and secreting surface. 



