16 A FLORA OP MANILA 



The outer row or whorl is known as the calyx, and is commonly green, 

 firmer in texture, and smalle^ than the next inner row; the individual 

 parts are called sepals. The next inner row or whorl is known as the 

 corolla, which is commonly larger than the calyx, of thinner texture, and 

 frequently white or variously colored; the individual parts are called 

 petals. Certain flowers in cultivated plants consist wholly of floral 

 envelopes, and these are known as double flowers, as in the rose, some 

 cultivated species of Hibiscus (gomamela) , etc. 



The next inner .whorl consists of the stamens , or male organs. A 

 typical stamen consists of two psCrts, a stalk, known as the filament, 

 vyhich bears a variously shaped body filled with a fine, yellow, dust-like 

 substance, the pollen, this body being called the anther. 



The innermost row or whorl, frequently a single body, is the pistil , 

 or female organ, which, when complete, consists of three parts, the ovary, 

 style, and stigma; a simple pistil is called a carpel. The ovary is the 

 basal, usually enlarged and hollow part, which contains one or more 

 ovules or rudimentary seeds; an ovary may be from 1- to many-celled. 

 The style is the usually tapering part above the ovary. The stigmo, is 

 a variously shaped, often small, usually apical part of the style with a 

 moist surface to which the pollen may adhere. 



As noted above a complete flower is one in which all four of the above 

 sets of organs are present. In very many ' flowers from one to three 

 of the sets of organs are absent, such flowers being incomplete. A perfect, 

 bisexual, or hermaphrodite flower is one in which the two sets of essential 

 organs, stamens and pistils, are present and fully developed, although 

 the perianth may be present or absent; an imperfect or unisexual flower 

 is one in which either the stamens or the pistils are imperfect or wanting. 

 Flowers with stamens and no or only rudimentary pistils are called 

 staminate or male, and those with pistils and no or only rudimentary 

 stamens are called pistillate or female. 



Unisexual or imperfect flowers are said to be monoecious when both 

 male and female flowers are produced by the same individual, as in 

 Rieinus communis (tangan-tangan) ; dioecious when male flowers are 

 borne on one plant and female flowers on another as in Antidesma 

 (bignay) ; and polygamous when som6 flowers are perfect, and some male' 

 or female on the same plant. 



Incomplete flowers are said to be naked when they have neither calyx 

 nor corolla, and apetalous when the corolla is absent. When there is but 

 one set of floral envelojies present it is always considered to be the calyx. 



Flowers are regular, when all the parts of each set of organs are of 

 like size and shape; irregular, when some parts of one or more sets of 

 organs differ from other parts of the same set either in shape or size, or 

 both. 



A symmetrical flower is one in which the parts of all sets of organs 

 are the same in number or in multiples of the prevailing number; an 

 unsyvimetrical flower is one in which there is a variation from the 

 standard number in one or more sets of organs. 



In the use of numerals in describing the parts of flowers they are 

 termed S-merous or trimerous, when the parts are in threes, 5-meroM or 

 pentarr„erous when the parts are in fives, etc. Plants with 1, 2, 3, or 

 many stamens, are described as monandrous, diandrous, triandroua, poty- 

 androus, etc. ; if with 1, 2, 3, or many petals, as monopetalout, dipetaloue, 

 tripetalous, polypetalous, etc. 



