200 PROCEEDINGS OF THE ACADEMY OF [18T9. 



The phenomena which, last year, were regarded as showing 

 great probability, if not convincing proof, of the contractile power 

 referred to, were: the grasping of a slender hair by said glands 

 with sufficient force to allow of the withdrawal of the pollen- 

 masses ; and a coincident change in the appearance of the jaws 

 or lips of the same glands. The facts are undoubtedly as stated; 

 but the circumstances attending; the change had been imperfectly 

 noted or their significance misinterpreted. The lips of the glands 

 in their primary, undisturbed position, which had been thought 

 to be separated by a sensible distance, allowing of the insertion 

 of the foot or proboscis of an insect were now seen to be thick- 

 ened and chamferred off along the upper edge, leaving a wedge- 

 shaped groove, but still touching one another at the lower surface. 

 No accidental or intended intrusion would therefore be successful 

 in reaching the inner surface of the cylindrical gland ; and by very 

 many experiments it was amply proven that no amount of touch- 

 ing or pressure upon the edges of this groove was followed by any 

 change of position. 



He then explained how the removal of these glands and their 

 associated pollinia was effected by insect agency, calling attention 

 to the narrow passage left between the rigid proximate edges of 

 the adjacent anthers; showing that it was widest at their lower 

 extremity, and quickly narrowing, led up into, and was continu- 

 ous or coincident with the before-named groove through the gland ; 

 so that the foot of fly or bee inserted below while the insect was 

 crawling over the flower, was almost necessarily drawn along it 

 until it reached and entered the gland. The very delicate attach- 

 ment of the latter to the stigma was then easily ruptured, and the 

 insect escaped, carrying glands and pollinia with it. Experiment 

 showed that it was only when the Hands were so far removed from 

 their proper position that the caudicles or arms connecting them 

 with the pollen masses were relieved from the restraint in which 

 they had been held on the curved surface of the stigma that their 

 lips complete^ closed upon the intended substance, giving them 

 the changed appearance formerly misunderstood. 



A comparatively high magnifying power and delicate manipu- 

 lation of the light further showed, just below the meeting edges 

 of the anthers, a series of fine spieula-like hairs inclined upwards, 

 having a tendency to guide into and restrain within the passage 

 any object which had once entered at the widened end. In some 

 species, noticeably in Araujia albens, the nectarial reservoir was 

 shown to be placed immediately below this opened passage, and 

 when the moths which frequent them thrust their proboscis down 

 into the tubular corolla in search of their honeyed food, they are 

 almost certain to be caught, not by the glands primarily, but by 

 these trapdike edges of the anthers. Here, according to many ob- 

 servers, they are held till they die; or, if successful in tearing them- 

 selves away, leave the entangled organ behind them in their flight. 



