854 3 Transactions. — iJulanij. 



some little interest for those naturalists engaged in the study of the varied 

 modes of fertilization in use among plants, I have drawn up the following 

 notes on the subject, 



Glossostigma elatinoides is a small, creeping, intricately branched moss- 

 like plant, generally found in wet swamps, or by the margins of lakes and 

 ponds, often growing entirely submerged. The flowers, which are axillary 

 on short peduncles, are very minute, hardly exceeding ^ inch in diameter. 

 The corolla has a short tube and five nearly equal spreading lobes ; the two 

 upper, however, are rather smaller and more closely united than the lower. 

 The margins of all the lobes are fringed with numerous minute cilire, and 

 the cellular tissue throughout is unusually lax. The stamens are four in 

 number, two long and two short, the anthers being approximated in pairs, 

 one above the other, as in so many of the Scroplndarinea. The style is 

 about the same length as the corolla. At the base it is nearly cylindrical, 

 and very slender, but above the middle it expands into a broad and thin 

 spoon-sha;:ed lamina, the anterior surface of which is quite smooth and 

 plane, but the back covered with delicate clavate papilla pointing upwards 

 towards the summit of the style. 



Oil examining a recently expanded flower, it will be observed that the 

 broad end of the style is abruptly doubled over towards the front of the 

 flower, thus covering the stamens and entirely concealing them from view. 

 If the point of a needle, or stifi" bristle, be inserted into the corolla, and the 

 front of the sLigma lightly touched, it at once s^u-ings up and uncovers the 

 stamens, moving back to the upper lip of the flower, to which it becomes 

 so closely applied that it is difficult to distinguish it from the corolla 

 without the use of a lens. After a short time the style gradually moves 

 inwards, and ultimately bends over the stamens as at first. With the view 

 of ascertaining the time which ela^jses before the stigma resumes its normal 

 position, I made the following experiment. At 9 a.m. I touched the 

 stigmas of seven fiowers, causing them to uncover the stamens and occupy 

 their position at the back of the flower. At 9"12 one of the styles had 

 commenced to move inwards; at 9-15. all had advanced a considerable 

 distance; at 9*20 five out of the seven covered the anthers as closely as at 

 first; at 9*25 the whole of the seven had resumed then" original position. 

 Further experiment also showed that the stigmas may be repeatedly touched, 

 but always retain then- sensitiveness until the flower commences to wither. 



It cannot be doubted that this irritability of the style is connected with 

 the fertilization of the plant — in fact, that it is solely a contrivance to 

 secure cross-fertilization possibly so arranged that if the flower is not visited 

 by insects self-fertilization is not ^Drevented. Let an insect crawl into the 

 flower, or let a larger one insert its proboscis ; it would be difficult for either 



