X OUTLINES OF BOTANY. 



asepalous, when there is no calyx. 



apetalous, when there is no corolla. 



naked, when there is no perianth at all. 



hermaphrodite or bisexual, when both stamens and pistil are present and perfect. 



male or staminate, when there are one or more stamens, but either no pistil at all or an 

 imperfect one. . 



femaU or pistillate, when there is a pistil, but either no stamens at all, or only imperfect 

 ones. 



neutm; when both stamens and pistil are imperfect or wanting. 



barren or sterile, when from any cause it produces no seed. 



fertile, when it does produce seed. In some works the terms barren, fertile, and perfect are 

 also used respectively as synonyms of male, female, and hermaphrodite. 



86. The flowers of a plant or species are said coUeotively to be unisexual or declinous when the 

 flowers are all either male or female. 



moncecious, when the male and female flowers are distinct, but on the same plant. 

 dioecious, when the male and female flowers are on distinct plants. 



polygamous, when there are male, female, and hermaphrodite flowers on the same or on 

 distinct plant?. 



87. A head of flowers is heterogavious when male, female, hermaphrodite, and neuter flowers, 

 or any two or three of them, are included in one head ; homogamous, when all the flowers 

 included in one head are alike in this respect. A spike or head of flowers is androgynous when 

 male and female flowers are mixed in it. These terms are only used in the case of very few 

 Natural Orders. 



88. As the scales of buds are leaves undeveloped or reduced in size and altered in shape and 

 consistence, and bracts are leaves likewise reduced in size, and occasionally altered in colour ; 

 so the parts of the flower are considered as leaves still further altered in shape, colour, and 

 arrangement round the axis, and often more or less combined with each other. The details of 

 this theory constitute the comparatively modern branch of botany called Vegetable Metamor- 

 phosis, or Homology, sometimes improperly termed Morphology (8). 



89. To understand the arrangement of the floral parts, let us take a complete flower, in which 

 moreover all the parts are free from each other, definite in number, i.e. always the same in the 

 same species, and symmetrical or isomerous, i.e. when each whorl consists of the same number 

 of parts. 



90. Such a complete symmetrical flower consists usually of either four or five whorls of altered 

 leaves (88), placed immediately one within the other. 



The Ca.lyx forms the outer whorl. Its parts are called sepals. 



The Corolla/ forms the next whorl. Its parts, called petals, usually alternate with the 

 sepals ; that is to say, the centre of each petal is immediately over or within the interval 

 between two sepals. 



The Stamens form one or two whorls within the petals. If two, those of the outer whorl 

 (thi outer stamens) alternate with the petals, and are consequently opposite to, or over the centre 

 of the sepals ; those of the inner whorl (the inner stamens) alternate with the outer ones, and 

 are therefore opposite to the petals. If there is only one whorl of stamens, they most frequently 

 alternate with the petals ; but sometimes they are opposite the petals and alternate with the 

 sepals. 



The Pistil forms the inner whorl ; its carpels usually alternate with the inner row of 

 stamens. 



91. In an axillary or lateral flower the upper parts of each whorl (sepals, petals, stamens, or 

 carpels) are those which are next to the main axis of the stems or branch, the lower parts those 

 which are furthest from it ; the intermediate ones are said to be lateral. The words anterior 

 (front) and posterior (baok) are often used for lower and upper respectively, but their meaning is 

 sometimes reversed if the writer supposes himself in the centre of the flower instead of outside 

 of it. 



92. The number of parts in each whorl of a flower is expressed adjeotively by the following 

 numerals derived from the Greek : — 



mono-, di-, tri-, tetra-, penta-, hexa-, 

 1-, 2-, 3-, i; S-, 6-, 



prefixed to a termination indicating the whorl referred to. 



93. Thus, a Flower is 



disepalous, trisepalous, tetrasepalous, polysepalous, etc., according as there are 2 3 4 or 

 many (or an indefinite number of) sepals. ' ' ' 



dipetalous, tripetalous, polypetalous, etc., according as there are 2, 3, or many petals 

 diandrous, triandrous. polyandrous, etc., according as there are 2, 3, or many stamens 

 digynous, trigynous, polygynous, etc., according as there are 2. 3, or many carpels. 



And generally (if symmetrical), dimerous, trimerous, polymerous, etc., according as there are 

 2, 3, or many (or an indefinite number of) parts to each whorl. 



