CYCAS 187 



the nucellus of the ovule which he took to be naked, missing 

 the very slightly indicated integument. He followed the pollen 

 tube to the tip of the embryo-sac and the development of the 

 endosperm in its upper portion, where the embryo appeared. 

 He saw the growth of the endosperm leading to its complete 

 protrusion from the ovule and inverting the embryo so that 

 its cotyledons point to the surface. Further he saw the long, 

 empty, absorbent caecum grow out from the hinder end of the 

 embryo-sac into the massive base of the young seed. 



This account is substantially correct in all its facts, and 

 Treub's work adds to it the cellular details of the origin of the 

 embryo-sac, the setting apart of the endosperm cell to grow into 

 the haustorium, and the details of segmentation of the embryo. 



Such vivid, accurate, description of strange facts, when 

 previous knowledge gave no clue, is in itself no mean scientific 

 achievement. 



To sum up Griffith's work on the morphology of the re- 

 productive organs of the Angiosperms we see that he added 

 many important facts and gave correct descriptions of what 

 still remain among the most anomalous ovules and embryos. 

 His methods did not enable him to distinguish clearly the 

 contents of the embryo-sac, and he accepted and confirmed 

 Schleiden's erroneous view of the origin of the embryo. But 

 this hardly detracts from the directness and consequent value 

 of all his observations. 



Turning now to the Gymnosperms, we find again that 

 Griffith devoted much attention to those forms that from his 

 residence in the tropics he was in a position to study with most 

 advantage. He describes in the Notulae his observations on 

 the ovules and pollination of various Coniferae and Gnetaceae. 

 But we may concentrate our interest on his work on Cycas. The 

 rough structure of the young seed had already been described 

 by Robert Brown who had recognised the gymnospermy of the 



group. 



But Griffith's descriptions and figures are much more accurate 

 are indeed far in advance of those of much later observers 

 and add greatly to our knowledge of this plant. These two figures 

 (pi. XVI) will speak for themselves and show how clearly Griffith 



