308 



NATURAL mSTOBY OF PLANTS. 



Cotoneaster thymlfolia. 



Medlar solitary, in the rest of the genus grouped into either short 

 racemes or corymbs, simple or composed of cymes. The difterent 

 axes of the inflorescence arise from the axils of bracts of successive 

 ages. 



Cofonenstcr^ differs essentially from Pi/rux and Crat(eguii in the 

 insertion of the carpels. Of these there are five, or more frequently 

 two or three, sometimes only one. They are free from each other, 

 and touch, without adhering, by the ventral angles of their ovaries. 

 But the base of each ovary, instead of being horizontal, is sliced off' 

 obliquely upwards and outwards, so that there is a broad surface of 

 insertion, applied not towards the bottom of the floral receptacle, 

 but over a large surface of the inside of the sac (fig. 406). Thus, 



the ovary is not very deep at the 

 back, but much deeper on the ven- 

 tral angle. Within, and near the 

 base of this angle, are inserted two 

 collateral descending anatropous 

 ovules, with their micropyles down- 

 wards and outwards." The styles 

 are free, of the same number as the 

 carpels, either diverging or close 

 together, and each ending in a 

 stigmatiferous head. On the edges 

 of the receptacular sac are inserted tlie perianth and audroceum, 

 and tlie interval between their insertion and that of the ovaries is 

 lined by a coloured glandular disk. The sepals are quincuncial, 

 the petals imbricated. The stamens are about twenty in number, 

 arranged as in Pyrus? The fruit of Cotoneaster is a drupe consisting 

 of from one to five stones imbedded in a fleshy receptacle.' In each 

 is an ascending seed, whose exalbuminous embryo has its radicle su- 

 perior. About fifteen species of this genus are known, shrubs or small 



Fig. 466. 

 longitudinal section of flower. 



' Meuik., Pfinnz. OetM., 17'J3.— LlNDL., 

 Trant. Linn. Sue. jciii. 101, t. 9. — DC, 

 J'rodr., ii. (>:{2. — Si'acii, Suit, a Buffon, ii. 

 73.— Endi... Gen., n. 6347.— Paykr. Orqanoq., 

 498, t. ccii. figg. 22-34.— H. H., Gen., 627 n 

 65. 



' They Imvo two coats. 



' There are, however, MiiecifM with Imt fifteen 

 BtnmcnH, which nmy he urniiipeil in twD ihlVerent 

 way", either in threen Huiterpimed to the ]ietuls, 

 and iiDiin tothe KepnlH, TiH ill ('. finm nt,,t,, I, ism 



or two stamens supcriHJscd to eju-h petal, and 

 one to enrh sepal. 



* Usually, indeed, this orpan, topofher with 

 the base of the calyx, is the only one to aciiuire 

 this consitiU-ncy in the fruit, for the ovaries 

 form little woody nuts, surniountod by the 

 withered styh-, and present no tniee of fleshy 

 tisNiie almve where tliey |>rojeet into the sacliko 

 cavity foriniHl by the upper part of the nvep- 

 ti.cle. Tlie stone is thin in C. denticttlntn H.H. K . 

 {\>,>,,-li.i LiM.i.., Hot. ifr'.y. (IHir.), .Viic. \0). 



