1907.| Wrinkled Peas, and their resultant Starch-grains. 127 
of the plants, five of each of whose seeds were preserved in the packets. So 
that I could find out in the case of the seeds in any given packet whether 
they were borne on a plant which produced only rounds, or both rounds and 
wrinkleds, or only wrinkleds. I wish particularly to emphasise the fact that 
this information was not written on the packets, but was obtainable by 
looking up, in the records, the plant represented by the number on the packet 
containing its seeds. 
I started by writing down the catalogue-numbers of each of the packets. 
Then I recorded the nature of the grains in the seeds opposite the number 
of the packet containing them. Not until I had examined all the grains 
did I refer to my records for the characters (whether D D, DR, or RR in 
respect of seed shape) of the parent plants of the seeds in the packet. 
I postponed this reference to my records until after all the grains had been 
examined, in order to prevent any possibility of the determination of the 
nature of the grains being influenced by a knowledge of the gametic 
constitution of the plant which bore them. 
Our interest centres chiefly on the possible difference between the round 
peas borne on plants bearing both round and wrinkled, and those borne on 
plants bearing only round. I shall, therefore, postpone reference to the 
contents of the 12 packets containing wrinkled peas until after I have dealt 
with the rounds. 
There were 36 packets containing round seeds. In every case—16—in 
which all the five seeds in a packet contained nothing but potato-shaped 
grains (and occasionally the very small compound grains found in “ Eclipse ”’) 
the plants bearing them had produced only round seeds. Table IL gives the 
details of these families, and fig. 5 shows the appearance of these extracted 
dominant grains.* It will be seen that they do not differ sensibly from the 
-grains of “ Eclipse.” 
The small compound grains, which are often exceedingly minute, are likely 
to be overlooked: the absence of any record of them in the first four families 
in Table II may be due to the fact that I did not detect them because I was 
not on the look-out for them. The presence of these grains in a pea is 
indicated in the table by the letters 7c. There was a single case (54.129.11) 
of an apparently compound large p-grain divided longitudinally into two; 
but the rarity of such a grain points to the conclusion that this case was due 
to an accidental fracture; which would be quite likely to occur during the 
scraping of the soaked pea with a razor. 
* [ have not measured any grains in F;. But no difference could be seen, between the 
A p-, c-, and r-grains in this generation and the grains, of these three types, already 
described. 
