QUINCE 407 



within the calyx-tube : the pome moreover is somewhat spherical 

 or conical with an indented base where it joins the peduncle. 



1 1. The Medlar {Pyrus germanica Hook.) is sometimes placed 

 in a separate genus and named Mespilus germanica L. Its 

 ' fruit ' is a roundish top-shaped pome to which are attached the 

 five large leaf-like sepals. The receptacle is hollowed out as in 

 the apple and pear, but it does not completely enclose the 

 carpels; the latter are consequently exposed within the broad 

 open calyx-tube. Each carpel, of which there are five, de- 

 velops a hard bony wall which protects the single seed within it. 



21. Allied to the medlar in structure of the fruit is the WMte- 

 thoru or Hawthorn {Cratcsgus Oxyacantha L.), so valuable for 

 hedges. 



The ' fruit ' when ripe is a scarlet round or ovoid pome, but 

 the upper part of the receptacle or calyx-tube is more con- 

 tracted than in the medlar and the sepals are small. The carpels 

 are usually only one or two in number : they develop hard. bony 

 walls. 



13. The Quince (Cydonia vulgaris Pers.) belongs to. another 

 genus of the Rosacese. 



The ' fruit ' or pome is hard and possesses a woolly surface 

 when young but is smooth when ripe. It resembles the pear or 

 apple in shape and structure, but within each of its five carpels 

 are many seeds arranged in two rows. The sepals at the apex 

 of the fruit are leaf-like. 



The testa of the quince seeds abounds in gum which with 

 water swells up into a mucilage. 



Ex. 214. — Compare the flowers of the apple and pear. In what do they 

 differ from each other ? 



Ex. 215. — Make longitudinal and transverse sections of the flowers of an 

 apple and a pear. Observe the position and extent of the receptacle and the 

 part of it termed the calyx-tube ; in each note also the number of carpels 

 and the ovules in the latter. 



Ex. 216. — Examine a half-grown apple and pear : observe the calyx- 

 tube. What part of the apple and pear flower is still visible in the fruit. 



