PlM.MKOSi: FLOWEIJS. '-VI') 



cation of the species, the aim of one being cross-fertilisation, 

 the aim of the other self-fertilisation, or autogamy. In the 

 pin-centres autogamy is practically impossible, in the rose- 

 centres it is clearly what nature intende'l. 



Now this being so, the question arises, is there a struggle 

 continually going on between these two forms, and is one 

 gradually supplanting the other ? Do the pin-centred plants 

 manifest any tendency to lose their stamens, and the rose- 

 centred plants their pistils, so that ultimately the Primrose 

 Avili become dioecious ? Or can it be that in course of time 

 these two forms will become more and more marked, and 

 eventually branch off into distinct varieties ? These are 

 interesting points for consideration, but before attempting 

 to theorise, it is plain that the first thing to do is to ascertain 

 which of the two forms predominates, or hoAv they are dis- 

 tributed. 



In order to gain some information on the subject with 

 regard to Guernsey, I arranged with my little son that Ave 

 should make a study of primroses during the spring of 1906. 

 Accordingly we began early in April, as soon as these flowers 

 were fairly numerous, and continued our observations until the 

 second week in .June, when primroses were about over for the 

 season, jotting dowm in our note-books the character of each 

 flower as we examined it, whether pin-centre or rose-centre, 

 and taking care throughout the whole time not to go over the 

 same ground twice. Also we made it a rule never to note 

 two floAvers that grew within arm's length of each other, 

 unless they diflered in character, a necessary precaution to 

 avoid the possibility of registering two flowers growing on 

 the same root, for of course all the blossoms of one plant are 

 uniform. Then after each walk our notes were classified, and 

 the numbers counted. Some of our excursions were short, 

 and some extended over many miles ; but all were conducted 

 on the same plan, and in a perfectly impartial manner. In 

 going along a lane, for example, if one hedgebank faced the 

 sun, and the other lay in the shade, my son would note the 

 flowers on one side, and I on the other. 



Now I confess that at the outset I fidly expected to find 

 one of the two forms strongly preponderating — perhaps the 

 rose-centres at one time, or in one locality, and the pin-centres 

 in another ; at any rate it appeared to me almost certain that, 

 owing to some cause or other, there must be a considerable 

 difference in their relative numbers. But I very soon dis- 

 covered that this was quite a mistaken idea — for on the 

 verv first day of our observations, when we had noted i^66 



