242 BIOLOGY. 



cacy, with cotemporaneous development and cotempo- 

 raneous death. 



1257. Not only are the ribs of the corolla, but those 

 also of the calyx, liberated to become filaments. There 

 are calyx- and corolla-filaments. 



1258. As ribs, the filaments must stand in the mid- 

 dle of their petals, i. e. opposite to them. 



1259. Filaments, which alternate with the parts of 

 the corolla, are consequently calyx-filaments ; such as 

 alternate with the lobes of the calyx, or stand opposite to 

 the petals of the corolla, are corolla-filaments. 



1260. Most filaments, and consequently the calycine, 

 are alternating in their arrangement. Most corollae 

 therefore have no longer strength sufficient to produce 

 filaments. 



1261. Flowers provided with opposite and alternating 

 filaments have consequently two circles of them, as is the 

 case in many Pinks. With the determination of the 

 number of filaments the race has been therefore spe- 

 cified. 



1262. The number of filaments stands in relation 

 to the parts of the corolla ; therefore three and five are 

 the prevailing numbers. 



1263. There is no absolute number in the filaments, 

 but only one of relation. Corollae with three petals have 

 invariably also three filaments, and those with five of the 

 former, the same number too of the latter. 



1264. The number of filaments is always the simple 

 or multiple of the parts of the corolla. Three calyx- or 

 corolla-parts have 3 X 1 r 3 X n> filaments. 6 is not 6, 

 but 3 X 2 ; 9 is 3 X 3 ; 10 is 5 X 2 ; 20 is 5 X 4 ; or 

 5x3+5X1, anc i so on- 



1265. The filaments do not simply follow the num- 

 ber, but also the conjunction, position and arrest, of 

 the corolla. They are epigynous, peri- or hypogynous. 



1266. In irregular corollae the filaments are usually 

 abortive ; as in those of the orchideous, labiate and papi- 

 lionaceous plants. 



1267. The arrest of the filaments usually stands in 



