MORPHOLOGY OF ANGIOSPERMS. 131 



corollas — one, as in lavender, where the mouth of the tube is open, 

 known as ringent ; and another, where the mouth is closed, as in 

 Linaria, called personate. 



There are a number of other special forms of calyx and corolla, 

 particularly the latter, and of these may be mentioned the follow- 

 ing : A corolla, like that of the harebell, which is more or less bell- 

 shaped, is termed campanulate; a more or less campanulate 

 corolla contracted near the opening, as in Gaultheria, is spoken 

 of as URCEOLATE or virn-shaped; in the morning glory and other 

 Convolvulaceae the corolla is said to be infundibuliform or 

 funnel-shaped (Fig. 174) ; a corolla, in which the limb spreads 

 abruptly from the tube, as in Phlox, is termed hypocrateriform 

 or salver-shaped; a corolla with a short tube and outspreading 

 limb, as in potato, is said to be rotate or wheel-shaped; a rotate 

 corolla with the margin more or less upturned is called crateri- 

 FORM or saucer-shaped ; in aconite the upper petal is hood- or hel- 

 met-shaped, the corolla is spoken of as galeate ; in the violets one 

 of the petals has a spurred appendage and the corolla is described 

 as saccate or calcarate, while the modified petal in the orchids is 

 known as the labellum. 



Duration of Calyx and Corolla. — There is considerable 

 difference in the length of time that the calyx and corolla persist, 

 not only with reference to each other but in different plants. The 

 parts are said to be caducous when they drop from the flower as 

 soon as it opens, as the calyx of the poppy ; when they remain for 

 a day or so, they are said to be ephemeral or fugacious, as in 

 the petals of the poppy ; in the rose and apple the petals fall away 

 soon after the pollen reaches the stigma and they are said to be 

 deciduous ; in some flowers the petals wither but persist until the 

 maturing of the fruit, as in the Droseracese, and are known as 

 marcescent ; the calyx may remain unaffected until the maturing 

 of the fruit, as in the Labiatce, when it is said to be persistent. 



Bracts. — In addition to the floral envelopes other more 

 or less modified leaves are borne on the flower branch below the 

 flower, frequently at the base of the flower stalk, and these have 

 received the name bracts. The bracts closely resemble the foli- 

 age leaves but usually are smaller and frequently are mere scales, 

 without chlorophyll. In some cases, however, they are large and 



