UMBELLIFLOKE. 493 



in all in the entire fruit) are placed opposite the calyx- teeth 

 and the others between them. In some genera there are in 

 addition 4 secondary ridges to each mericarp between the primary 

 ones (Fig. 528 E : the secondary ridges bear the long bristles). 

 Inside these secondary 'ridges, or inside the grooves between the 

 primary ridges, when the secondary ridges are absent, oil ducts 

 (vittse, schizogenous ducts) are found in the pericarp, most fre- 

 quently one in each groove ; two are also often found on the 

 ventral side of each mericarp (Figs. 528 E, 530 oZ, etc.). The seed 

 is most frequently united with the pericarp. The embryo is small 

 and lies high up in the large, most frequently horny endosperm 

 (Fig. 528 _D). The endosperm does not contain starch, but oil, 

 and presents three different forms, of important systematic value : 

 (a) those which are quite flat on the ventral side (i.e. the side 

 turned towards the plane of splitting) (Figs. 528 #, 530, 531, 534, 

 etc.) : the majority of the genera, ORTHOSPERME^ (e.g. Carum, Pas- 

 tinaca) ; (b) those in which the endosperm on the ventral side is 

 provided with a longitudinal groove, often deep : CAMPYLOSPERME.E 

 {e.g. Anthriscus) ; the transverse section is nearly a crescent ( Fig. 

 532); (c) those in which the endosperm is concave on the ventral 

 side (hollow in both longitudinal and transverse sections) : CCELO 

 SPERMEJ: (e.g. Coriandrum) (Fig. 538). 



The genera are distinguished first of all by the endosperm and forms of fruit, 

 the ridges and oil-ducts ; then by the form of the umbel, the calyx and corolla, 

 by the absence or presence of an involucre, etc. 



I. HYDROCOTYLE^E, PENNY-WORT GKOUP. Capitula OY simple umbels 

 (all the other groups have compound umbels). No oil-ducts. 

 Orthospermous. Hydrocotyle (Penny- wort). 

 The fruit is considerably compressed laterally 

 (Fig. 529). .The calyx-teeth are small. The 

 leaves are peltate. Didiscus. Sanicula (San- 

 nicle). The umbels are small, capitate, gener- 

 ally collected in a raceme; calyx-teeth distinct. 

 $ and $ -flowers in the same umbel. The 

 fruits are round, studded with hooked bristles. 

 No carpophore. Astrantia has an umbel sur- 

 rounded by a large, often coloured involucre, 

 with this exception it is the same as the pre- FiQ.52Q.-Hydrocotyie 

 ceding, but the fruit is slightly compressed, 

 with 5 equal ridges. Hacquetia (Dondia). 

 Eryngium (Sea Holly) : leaves often thorny. The flowers are all 



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