422 Journal of the Asiatic Society of Bengal. [November, 1914. 



fewer in number , and the portion of the spadix occupied by them 

 is about half that taken up by the staminate flowers (Fig. 4). 



On examining a spathe at sundown, when the strong un- 

 pleasant odour is being given off, it will be found that the 

 narrow constricted part is open, forming a passage down into 

 the lower chamber, where the pistillate and thread-like neuter 

 flowers are concealed (Fig. 1). 



The margins of the spathe at the constriction are wide 

 apart, and the slender portion of the spadix stands close 

 against the spathe, leaving a clear passage down into the tube. 

 At this, the first stage, the stigmas are very sticky and the 

 strong carrion-like odour is given off from the pistillate flowers: 

 but the staminate flowers will be found to be still immature, 

 with no pollen shed. If examined on the following morning, 

 when in the second stage, the spathe will be found to present 

 a very different appearance. There is no disagreeable odour 

 and the beautiful upper portion of the spathe is hardly recog- 

 nizable, having faded into a dull pale purplish colour and fallen 

 back, away from the spadix, with the tip dangling on the ground 

 (Fig. 2). The opening leading down into the tube is also closed 

 by the margins of the spathe having overlapped tightly round 

 the base of the staminate portion of the spadix (Fig. 2 and 

 plant to left in Fig. 3). In the afternoon the opening will 

 still be found closed ; but on closer examination the staminate 

 flowers will be found to have started shedding their pale pink 

 pollen. On the following morning, when in the third stage, 

 the spathe will be found in a still more faded condition, and 

 the whole of the exposed part of the spadix, consisting of the 

 appendage and staminate portion, also fallen back, and the pas- 

 sage into the tube again wide open, but not quite as fully open 

 as on the evening of the first day. At this stage the stami- 

 nate flowers have matured and have shed all" their pollen. 

 The pollen collects at the mouth of the tube and on the 

 spathe. The upper part of the spadix, having fallen back 



over the spathe, prevents the pollen from falling into the tube 

 (Fig. 4). 



On cuttting open the tube of a spathe in the second stage, 

 when the passage i3 tightly closed, a number of small brown 

 Lamplhcorn beetles (belonging to the dung-frequenting sub- 

 family Coprini) will be found imprisoned inside. The\ had 

 evidently been attracted into the spathe by the strong disagree- 

 able odour during the first stage, when the passage was wide 



open, and they were being kept prisoners till their release in 

 the third stage. 



It is clear that the floral mechanism of the spathe is of th< 

 nature of a trap, and by this ingenious method the plant 

 ensures cross-pollination, for the beetles carry the pollen from 

 on? spathe to another. 



Observations made by me on the opening and closing of 



