INFLORESCENCE. 



68 1 



amentum (fig. 777 [2]) ; a spike, usually pendulous, which falls off, rachis and 

 all, by an articulation, as in the willow or hazel. 3. The spadix, a thick 

 fleshy spike (fig. 777 [3]); examples, arum and calamus. 4. The cone, a fruit- 

 bearing spike, covered with scales (fig. 777 [4]) ; examples, the conifera. 5. The 

 raceme* cluster, a spike with the flowers on longer pedicels (fig. 778); exam- 

 ples, the currant. 6. The panicle, a branching raceme (fig. 779, Yucca gloriosd). 

 7. The thyrsus, a dense panicle, with longer peduncles in the middle than 

 at the extremities ; example, lilac. 8. The corymb, a raceme, in which the lower 

 flower stalks are elongated and raised to nearly a level with the upper 

 (fig. 780) example, ccrasus mahaleb). 9. The compound or branching corymb, 

 a corymb in which the secondary axis again sub-divides ; example, Pyrus ter- 

 minalis. I o. The umbel : in this form the primary axis is greatly depressed, and 

 the peduncles arise from a common point, and spread out like radii of nearly 

 equal length, a whorl of bracts (involucre) surrounding the common base. 

 In the compound umbel (fig. 781), Daucus carota, the secondary axis 

 ends in small umbels surrounded by bracts, which is termed an involucel. 

 This is observable in the umbelliferous plants carrot, parsley, hemlock, etc. 



A very peculiar kind of inflorescence, which characterises the great family 

 of the composite, is illustrated by 

 fig- 783. We see here theenlarged 

 floral axis or receptacle, a, sur- 

 rounded by several whorls or bracts, 

 bb, which constitute a general 

 involucre; the membranous bracts, 

 {palece), b' b', seen in the recep- 

 tacle, bear in their axils the sessile 

 florets, c and d, which either have 

 a calyx, ee, or not. The florets 

 on the receptacle are either all of 

 them tubular (d) or ligulate 

 (tongue or strap-shaped) ; florets 



(c) are associated with the tubular ones. The receptacle is not always flat, 

 but frequently presents a convex, globular, conical, concave, etc., shape. 



In the absence of palece the receptacle is said to be naked. The florets 

 at the margin, or circumference, are termed marginal flowers, w flowers of tJie 

 ray; the florets in the disc (centre}, central flowers, w flowers of the disc. 



Some plants bear male and female flowers on the same stem. These 

 are termed monadons plants. The oak is an instance. The diaecious plants 

 are those which bear stamens and pistil, or separately, on different plants, like 

 willows. We will now glance at the functions of the stamens and pistil. 

 The ovule has been mentioned as a tiny body in the ovary, and it consists of 

 a nucleus, and cellular tissue surround it, leaving a small hole called the 

 micropyle, into which the pollen tube enters after passing through the ovary. 

 As in the animal creation, the unions of different families succeed best ; no 

 close relationship will fertilize so well aswith other flowers. 



