510 Transactions of tlie Society. 



CuPULiFER.^5. — The Cupiilifera?. are, as a rule, anemophilous with 

 spherical dry pollen, which subsides into a 4-6 sided disk. 



The pollen of the Beech (Fagus) as it dries assumes a broadly 

 oval form with three furrows ; that of the Oak (Quercus robur) 

 subsides into an oblong-ellipsoid form, with broad rounded or sub- 

 truncate ends and three well defined furrows. The end view is 

 nearly orbicular. 



The Spanish Chestnut approaches still more to the common 

 entomophilous type, as it shrinks into an oblong-linear form with 

 three furrows, and is somewhat viscid. 



Salicace^. — This order contains two large genera : the Willows 

 and the Poplars. Willows are entomophilous, with the usual ellip- 

 soid pollen, rounded at the ends, with three furrows and viscid. 

 Both the male and female catkins have nectariferous glands and 

 are much visited by insects. Gradually the pollen becomes dry, 

 and in this state some of it may be carried by the wind to the 

 female flowers. 



Poplars on the contrary are essentially anemophilous. The 

 pollen is spherical and dry. It gradually assumes the disk form with 

 5-6 facets and obtuse angles. The stigmas of SaUo: have papillae 

 2-4 times as long as thick. Those of Populvs are broader and more 

 or less deeply 3-lobed, the surface consisting of large domed cells, 

 which are distinctly viscid. These characters resemble those wliich 

 occur in other anemophilous genera, such as Myrica, Alnus, Betula, 

 and Cory his. 



EMPETRACEiE. — The pollen is in tetrads, the four grains being 

 arranged in pairs crosswise. Each grain is roundly ovoid or 

 almost globular, with three depressions, two on one side and one 

 on the other. 



Conifers. — The Coniferse are anemophilous. The pollen grains 

 are first spherical. Those of Pinus sylvcstris subside into a hemi- 

 spherical or shortly bqat-shaped form, with two nearly globular 

 bladders or air-floats. Such pollens occur in F. montana, F. mu- 

 ricata, and Abies nohilis, while other species oH Finus smd Abies have 

 a similar arrangement, differing only in details. The pollen of 

 Cedrvs resembles an oblong boat with turned up ends, which corre- 

 spond with the air-floats of Finus. Microcachrys tetrcujona has 

 three floats. 



The pollen of Cuprcssus and Taxus is spherical ; that of Juniperus 

 (fig. 65) is faceted. On the other hand that of Fhyllocladus ylcmca 

 is ellipsoid, more or less narrowed at the ends. 



Orchidace^. — The pollen is in tetrads, or forms pollinia, the 

 separate grains being held together by glutinous matter. Cypri- 

 pedinm, however, is an exception, having powdery pollen. It has 

 moreover two fertile anthers, the other Orchids having only one. 

 These differences evidently have reference to the manner in which 



