460 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



flowered yet in this country, but I hope in the near future 

 attempts to raise them will prove more successful. 



The Influence of Foreign Pollen on the Ripening of 



Seed-pods. 



In the Orchid Review, iv. p. 41, Mr. T. L. Mead, of 

 Oviedo, Florida, U.S.A., writes : — " I note a great difference in 

 the time required to ripen seed-pods, according to the species of 

 pollen made use of : it seems to tend to a mean between the 

 normal ripening time of the two parents." The writer gives 

 several curious and interesting facts in support of his opinion, 

 and in three cases at least there appears to be some ground for 

 the theory. On the other hand, Mr. Cookson writes (Orchid 

 Revieiu, iv. p. 112) : — "From careful observation I am strongly 

 of opinion that the period necessary to produce fertile seed 

 depends on the period usual with the mother parent, and that 

 the male parent has little to do with it." In Orchid Revieiv, 

 iv. p. 326, Mr. Mead gives some exceptions to his former theory, 

 and suggests that the influence of the foreign pollen may be 

 individual rather than general. For instance, " Laalia anceps 

 pollen seems invariably to cut down time needed to ripen pods 

 of Cattleya labiata group by about six months ; while the pollen 

 oi C. labiata does not appreciably lengthen the time needed by 

 L. anceps pods to ripen. . . . Broughtonia sanguinea, which both 

 with its own and with foreign pollen ripens its seeds in one-and- 

 a-half to two months, has power to quicken the ripening of 

 C. Bowringiana, with which it gave good seed in eight-and-a- 

 half months." 



It seems to me that in the foregoing instances one of the 

 main factors in the period of ripening seed-pods has been over- 

 looked, and that is the time of the year when these experiments 

 were carried out. For instance, to take the case of L. anceps. 

 On January 22, 1896, I pollinated L. a. Sanderiana with its own 

 pollen ; the seed-pod ripened good seed by June 15, 1896, or 

 145 days. On January 27, 1897, I crossed the same plant again 

 with its own pollen, and it did not ripen its seed-pod until July 

 14, taking 169 days, showing a difference in period of ripening 

 (for the same plant pollinated by same plant) of twenty-four 

 days in two different years. This seems to show clearly that 



