On the Species of the Genus Primula in Essex. 167 
produced by each umbel is almost exactly identical with that 
produced by the plant. It will be seen that the s. are the 
most fertile in the proportion of 4 to 3. Of the s. flowers 14 
bore no seed, but more than double as many of the L, viz. 31, 
were barren. The four highest numbers of seeds produced 
by the s. are 97, 101, 104, and. 106 ; and the four highest 
numbers of seeds produced by the 1. are 70, 75, 76, and 90. 
The former were all, however, on one plant, but their lowest 
number is higher by 7 than the highest of the latter. 23 
P. viscosa. —At the end of August I gathered capsules from 
plants growing in two places near St. Moritz. Many had 
already shed their seed and a number of capsules burst, and 
so were spoiled (particularly of the s.) before I counted 
them. Table XV. shows that the two forms produce on an 
average exactly the same number of flowers per umbel, but 
that each flower of the s. produces 22 and the 1. 15 seeds ; 
while the product of each umbel is almost exactly in the 
same proportion. Of the s. capsules 14 produced no seed 
against no less than 51 in the 1., or nearly 4 to 1. The four 
highest numbers produced by the s. are 49, 49, 51, and 57; 
and the four highest numbers produced by the 1. are 55, 55, 
59, and 64. This is different from usual, as the highest 
numbers are generally on the side of the s. 24 
P. latifolia. —I have counted a few (605) seeds belonging to 
this species, but for some reason the flowers had never been 
fully fertilized—no less than 75 per cent, producing no seed. 
The s. produced 8 capsules an umbel to 7 in the 1.; the s. pro¬ 
duced 52 seeds per umbel, the 1. 63; the s. produced 7 seeds 
per capsule, the 1. 9, so that in this case, as with the 
Cowslip, the most fertile flowers were the long-styled. 
Probably it will be found (as Darwin says is the case with 
P. sinensis ) that the corolla in falling off (as it does with 
this species and the last) drags the anthers over the stigma, 
thus rendering the 1. most fertile; but I shall recur to this 
subject. 
23 [We learn from Muller’s ‘Die Befruchtung der Blumen ’ that Primula 
farinosa occurs both on the Alps and in North Germany, and probably 
owes this wide distribution to the mild climate succeeding the Glacial 
period. On the Alps, where it is visited by Lepidoptera in great numbers 
(Muller noted forty-eight species), the entrance of the flower is narrower 
than in North Germany, where butterflies and moths are less plentiful, 
and where the plant has probably to depend for cross-fertilization upon 
the visits of bees.— Ed.] 
24 The table is, however, seriously wanting in one particular. It does 
not show the average number of umbels produced by each plant of each 
form. This is because the plants of this species grow so thickly clustered 
together on the rocks that I could not distinguish one from the other. 
