288 Journal of the Asiatic Society of Bengal. [N.S., XIIT, 



The standard is erect in open flowers and acts as a signboard. 1 

 It possesses two dark streaks functioning as nectar-guides, 

 converging basally to a pair of thick fleshy swellings. The 

 bright red wings are the resting place for the pollinating insect 

 and they assume the form of a platform, being united with 

 the keel by interlocking folds about their middle, and the union 

 is effected by a projection on the keel fitting closely into a corres- 

 ponding pit on the wings on either side. In open flowers it 

 is impossible to separate them without tearing the parts, but in 

 very young buds fehe parts are separable. The wings have 



folds at their free edges on the staminal column near the 

 base. 



The keel has a claw, which by the >un's action bends and 

 exerts a strong downward pressure on the ovary. It has also a 

 fold of its free edge on the staminal column (enclosing the 

 ovary) on either side in front of the fold of the wings. The 

 keel is narrowed near the apex, slightlv holding the tip of the 

 stammal column. 



The diadelphous stamens, of which the mil here are disposed 

 m two sets, one closely behind the other, are slightlv protan- 

 drous and the anthers dehisce in the flower before explosion. 



The style slightly projects out of the staminal column in 

 order to keep off the stigma from the pollen liberated a little 

 lower down in the keel by the bursting of the anthers. 



Ihe flowers being red * and the pollen grains being sfcickv, 

 A. rugosus is evidently pollinated bv insects usuallv belonging 

 to the order Hymenoptera. 



Haying studied the structure of the flowers we may proceed 

 to examine the process of pollination in nature. 



In full sunshine the flowers open and become readv for 

 pollination, and it is at this time that the insect-visitors 

 frequent the plants. 



''■ One must not be annoyed," savs the great Snrengel, " at 

 navmg to spend a long time near a flowering plant, for it is not 



always visited forthwith by the particular insect which is 



c esigned to fertilize it," and I had to wait and watch for three 



aays before ] discovered the particular insect which visits 

 A. rugosus. 



Wf A1 i h ° Ugh Several insec ts, including one or two small 

 Dutternies many black ants, a few small beetles and a bug 



21 f*n ?,u n « hG plant ^ a bee > Nomi « ozybeloides. alone is 

 abo , n . ? er , mechanism m moti °n, therein bringing 

 about normal fertilisation. The other insects ' visit the 



ZSLfV** t0 8te al nectar and pollen from the 



eTmWWi '«„ 1 t, ai UCT1,ar ana pouen irom *>** 

 exnosfonH f S i , Failin 8 visits from ylmia oxybeloides, 

 explosion does not take place. The pollen often gains acce. 



*ouuuooK ot Mower Prvllmat.v^ ™i t «~„~„ an <* 



ower Pollination, vol. I, pages 69 and 196. 



