MORPHOLOGY OF HIGHER PLANTS. 419 



carp. Drupes are superior when they are free from the torus, as 

 in prune ; inferior when the torus forms a part of the fruit, as 

 in pimenta. Drupes are also spoken of as " dry " when the sarco- 

 carp is less succulent, as in Rhus glabra, or when they are col- 

 lected unripe, as in pepper, pimenta, and cubeb. The fruits of the 

 raspberry and blackberry consist of a collection of little drupes, 

 the whole being known as an ET.ERIO. In the blackberry the 

 drupelets cohere with the fleshy torus, while in the raspberry the 

 drupelets cohere with one another, forming a cap which is sepa- 

 rable from the cone-shaped torus. If the drupelets of the rasp- 

 berry are examined closely it will be found (Fig. 243) that each 

 has from 4 to 7 facets on the sides formed by the pressure of the 

 adjoining drupelets. These facets are usually slightly convex or 

 concave. Tschierske states that the individuals cling together, 

 first, because of the closely-fitting adjoining facets, the slightly 

 convex surface of one fitting into a corresponding concave surface 

 of another; and, second, because of the interlocking of the sinuous 

 hairs. 



A Follicle is a dry, dehiscent fruit which consists of one 

 or more separate carpels, the dehiscence being usually along the 

 ventral suture (Fig. 239) ; in Delphinium the carpels are single ; in 

 aconite from 3 to 5, and in star-anise (Illicium) from 7 to 8 ; in 

 magnolia the carpels are numerous, forming a kind of succulent 

 cone, and dehisce along the dorsal suture. 



A Galbalus is a berry-like fruit, formed by the coalescence 

 of fleshy, open scales, as in juniper (Fig. 75). 



Hesperidium.- -The fleshy, indehiscent, superior fruit of citrus, 

 as lemon and orange, is known as a hesperidium. The pericarp 

 is more or less coriaceous, and from the inner walls secretion hairs 

 develop, which contain sugar and an acid cell-sap, these consti- 

 tuting the fleshy portion in which the seeds are embedded. 



A Legume is an elongated, monocarpellary, usually dry, 

 dehiscent fruit, in which dehiscence takes place along both sutures, 

 the carpel thus dividing into two halves, or valves, as in the garden 

 pea (Pisum) and other members of the Leguminosse (Fig. 231). 

 In some cases legumes are jointed or articulated and indehiscent, 

 breaking up at maturity into a number of parts which are dis- 

 persed in much the same manner as samara-fruits, as in Meibomia. 



