a a Ee eee ae ee ee a ee ee 
THE DISPERSION OF BRITISH PLANTS. 251 
pecies. Average. 
175 Annuals 4 : i 4 = : 6°35 
31 Annuals or Biennials . : é ‘ 6°13 
23 Biennials : % : ; 5°44 
229 Total Monocarps . ‘ f 3 . 6°23 
296 Perennials . ? ; P : ; 7°31 
27 Doubtful duration . ‘ 6°70 
_Of the representative orders selected by Professor De Candolle as 
being gely composed of annual species, the principal is that o 
Dispersion according to Character of the Flower. 
| Structure.—Our sixty-one Cryptogams average 9°51, while our 
Phanerogams compare as follows :— 
species. Average 
172 Thalamiflorz . 5 ‘ ‘ ; 6:98 
205 Calyciflore: : 6°52 
306 Monopetalee 6-41 
talee 6°84 
7 475 Votal Exopens 2° OEY ee 
129 Petaloidess " , : : 7°23 
186 Glumacee i ; ' é 4 7°55 
315 Total Endogens . es : ‘ : 7°45 
Conspicuous Flowers.—Mr. D has shown how important a 
part is played by insects in the fertilisation of flowers; and how great 
a benefit is the cross-fertilisation effected by their means. e 
i erful 
ts that all plants with pape reir eg golateeed ge nee 
_ not only that it is so, but also that plants with white flowers are 
widely dispersed than those with coloured, a result I was not 
d som ‘ ' Oh 
thie’ of our Violets, Thistles, and Campanulas are intermed _ 
respect ; having a more limited range than those whose flowers 
Or egrgeee  e eg eae 
“The quotation is from Dr, Hooker's Address to the British Association. 
