302 Transactions of the Society. 



the willows suggest to us how plants may have originally passed 

 from anemophilous to entomophilous fertilisation. 



In the species with large edible fruits (hazel, oak, Spanish 

 chestnut, etc.), as in some other similar cases, the cotyledons are 

 thick and fleshy, and remain in the seed. In the two former they 

 are piano convex, and each occupies one-half of the interior of the 

 nut, to which it conforms. Those of the Spanish Chestnut are 

 more or less wavy, and ruminate, or unequally folded. 



The fruits are more or less inclosed in a cupule or involucre. 

 In the Birch it takes the form of a scale consisting of a bract and 

 two bracteoles, connate into one piece, trifid at the apex, and falling 

 with the nutlet. They closely overlap one another, forming a 

 cylindrical spike. In the Alder they form an oval spike, and the 

 scales when mature spread out, and let the nutlets drop away. 

 In the Hornbeam to the right and left of the bract there is a three- 

 lobed bracteole, partly enveloping the nut, enlarged and leafy 

 upwards, especially the one in the middle. 



In the Hazel there are two greatly enlarged bracteoles, more or 

 less toothed or fringed at the margins. There are originally two 

 ovules in each cell, but only one comes to maturity. 



The cupule of the Oak consists of many bracteoles, united 

 into one piece but carried with the free imbricated points of the 

 bracteoles. It forms the well known cup in which the acorn sits. 

 There are two ovules in each cell, but only one matures. 



The fruits of the Spanish Chestnut are inclosed, two or three 

 together, in a cupule of four pieces, which are densely covered 

 with long prickles. These open when the fruit is ripe, but serve 

 to protect it when young, and also, no doubt, assist in its dis- 

 semination. In this species also there are two ovules, but only 

 one seed. 



The cupule of the Beech consists of four lobes or valves, 

 covered on the back with numerous loose, pointed scales, perhaps 

 representing the original bracteoles. It incloses two or three 

 fruits, which are more or less winged at the edges. The coty- 

 ledons are folded up like a fan, so as to occupy the interior of the 

 nutlet. 



The seeds of the Willow (Salix), as already mentioned, are 

 minute, furnished with long silky hairs, and further lightened by 

 a hollow, not being quite filled by the embryo. 



In the Poplar also the seeds are minute, and have a parachute 

 of silky hairs. The fruits are very varied in form and structure. 



In some (Willows and Poplars) the fruits are minute, and 

 provided with, and carried about by long silky hairs ; in the Birch 

 and Hornbeam they are winged, and transported by the wind ; in 

 others (Oak, Beech, Hazel, Spanish Chestnut, etc.) they are large 

 and carried about by animals as food. The fruit of the Alder, 



