. The Indiana weed book. Weeds. 42 THE INDIANA WEED BOOK. the achene always has hvo scars, one at the base showing where it was joined to the floWer-stalk, and the other at the top where the style or stigma was united to it, whereas the seed has hut one scar indicating the point where it was joined to the ovary. The ripened pistils of the buttercups and the so-called seeds of the dandelions, catnip and hound's tongue are examples of achenes. The utricle is an achene with a thin, loose outer covering, as seen in pigweed, lamb's quarters, etc. The caryopsis or grain is a dry indehiscent fruit in
. The Indiana weed book. Weeds. 42 THE INDIANA WEED BOOK. the achene always has hvo scars, one at the base showing where it was joined to the floWer-stalk, and the other at the top where the style or stigma was united to it, whereas the seed has hut one scar indicating the point where it was joined to the ovary. The ripened pistils of the buttercups and the so-called seeds of the dandelions, catnip and hound's tongue are examples of achenes. The utricle is an achene with a thin, loose outer covering, as seen in pigweed, lamb's quarters, etc. The caryopsis or grain is a dry indehiscent fruit in which the seed is firmly united with the wall of the ovary, so that both fruit and seed form one body, as in wheat, corn and the weeds of the grass family. The dry dehiscent fruits are also numerous in kind. Among. Fir. 14. Illustrating forms of fruitsj a, single drupe of blackberry split to show pulp, stone and inner seed; i, a berry; c, pyxu of purslane, the lid upraised; d,.utricle of lamb's quarters; e, utricle of pigweed opening all iround;/, achene of buttercup: g, same SDlit lenethwisa fai show the mutineer! aoorl- h o M/V,/.- .â , m,,._ »i a uhts, c, pyxis or , tne M upraised; d,.utricle of Iamb s quarters; e, utricle of pigweed opening all around; /, achene pi buttercup; g, same split lengthwise to show the enclosed seed; h, a fottick; i, silique of a mus- tard; ;, capsule of a bt. Johnswort; *, a pod or legume; I, lament or jointed pod of a tick-trefpil. (After Gray.) them are the pod of the weeds of the pea family, which splits along both sides into two valves; the follicle of the milkweed, which splits down one side only: the capsule or fruit of a compound ovary, which usually splits lengthwise into several valves, as in the corn cockle, , discharges its seeds through chinks or pores, as in the velvet leaf, or bursts irregularly as in the lobelia; the silique of the mustard family, a pod which splits into two valves leaving a thin part
Size: 2190px × 1141px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectweeds, bookyear1912
