| 3 | .. | 3 Lythraceæ | .. | 1 | .. | 8 | .. | 9 Loasaceæ | 1 | .. | .. | .. | .. | 1 Cactaceæ | 3 | 1 | .. | .. | .. | 2 Cucurbitaceæ | .. | 2 | .. | .. | 1 | 3 Umbelliferæ | 8 | 33 | .. | 2 | 2 | 45 Araliaceæ | .. | 3 | .. | .. | 3 | 6 Cornaceæ | .. | 11 | .. | .. | 2 | 13 |---------+--------+--------+--------+---------+-------- Total | 164 | 283 | 71 | 136 | 87 | 741 --------------+---------+--------+--------+--------+---------+-------- Yellow appears to have been the first color developed, and flowers with this coloration are usually simple and regular in structure, as the buttercups and five-fingers. But why, it will be asked, should yellow have been the primitive color? The spores and spore-cases of the club mosses, and the pollen of all cone-bearing trees, and, in fact, of most plants, are yellow, and the yellow coloration of the first petals is doubtless correlated with this fact. Flowers of this tint are peculiarly attractive to yellow-banded flies, and when dull are avoided by beetles. Yellow flowers vary greatly in size, but pale yellow flowers are usually small, and bright or orange-yellow are large. _Ranunculus abortivus_ and _R. sceleratus_, which grow in wet places, are small and pale, while _R. bulbosus_ and _R. acris_, the familiar buttercups of our meadows, are an inch broad. An apparent exception to the above rule is offered by the globe-flower (_Trollius laxus_), found in dense swamps, which has solitary, very large, pale greenish-yellow flowers. As the cultivated European and Asiatic species have bright yellow flowers, the coloring of the sepals of _T. laxus_, for the petals are wanting, has probably retrograded from growing in dense shade.