THE PROPORTION OF PARTS IN FRUITS 311 



Table illustrating the Growth of the Acorn (Quercus Robur) 



AS REVEALED BY THE BALANCE, DURING THE SIX WeEKS PRECEDING 



ITS Detachment from the Cupule, from Observations made 

 BY THE Author at Salcombe, Devonshire, in 1908 and 1910. 

 (The cupule is not included in these observations.) 



Date 



when 



gathered, 



1910. 



Sept. 



Oct. 



13 

 20 



27 



4 



II 



1908. 



Sept, 

 11 



t) 

 Oct. 



Condition and state of 



attachment of the fruit to 



the cupule. 



J4 



^Firmly attached by liv- 

 1 ing tissue to the 

 1 cupule ; pericarp 2 

 ( mm. thick and moist 

 / Attachment looser ; be- 

 \ ginning to turn brown 

 Easily detached, but still 

 a slight biological 

 connection ; brown- 

 ing pericarp thinner 

 and drier 

 Falls at a touch from the 

 cupule ; well browned 

 After keeping for some 

 time and no longer 

 losing weight, pericarp 

 very thin, 0-3 mm. 



' Firmly attached to 

 cupule ; pericarp 

 thick and moist, 



Attachment loosening ; 

 browning ; pericarp 

 I thinner and drier 



Vital connection 

 severed ; falls at a 

 touch from the cupule 



After keeping for some 

 months and no longer 

 losing weight 



Average weight 



in grains of a 



single fruit and 



its parts (10 nuts 



in each case). 



Total. 



57 

 26 



56 

 62 



62 

 71 

 64 



35 



Peri- 

 carp. 



i8-2 

 21 '6 



i9'o 

 i5'3 



17-1 



24*6 

 29*1 



i8-i 



Seed, 



13-8 

 24-4 



31-0 

 357 

 357 



39'9 



31 4 

 32-9 



52-9 



Relative 

 weight of 

 the pericarp 

 and seed, 

 taking the 

 entire fruit 

 as 160. 



Peri- 

 carp, 



57 

 47 



38 

 35 

 30 



30 

 19 



44 

 47 



25 '5 



18 



Seed, 



43 

 53 



62 



65 



70 



70 

 81 



56 



53 



74-5 



Loss of weight 

 after drying in air 



at the ordinary 



temperature, stated 



as a percentage of 



the weight in the 



moist fruit. 



Seed, 



70 "o 

 67-8 



59-2 

 56-8 

 41*0 



43 '5 



the fresh fruit as lOO, the shell makes up 38 and the seed 62 

 parts of the whole. When this fresh acorn is allowed to dry- 

 in ordinary air, until it ceases to lose weight and exhibits 

 merely the usual hygroscopic variations regulated by the 



