ORGANS OF REPRODUCTION. 



241 



the Polygala {fig. 736), they are situated at the base or hilum 

 of the seed ; in the Asarabacca {fig. 737), Chelidonium and 



Fig. 735. Progressive development of the arillode of Euonymm. 

 a. Arillode. /. Funiculus. 1. represents the youngest seed ; 2 

 and 3. the progressive development of the arillode; 4. the oldest 

 and fully developed seed. 



Violet on the side, in a line with the raphe ; while in the Spurge, 

 thej are placed at the exostome. Some wTiters consider these 

 caruncles as forms of the aril, of which they then distinguish 

 four varieties, namely: — 1. The true arillus, as in Nymphcea 

 {fig. 734, A, a) ; 2. The arillode or micropylar arillus, as in 

 Euonymus {fig. 735, a); 3. The raphian arillus, as in Asa- 

 rum {fig. 737) ; and 4. The chalazal arillus, as in Epilobium 



Fig. 737. 



Fig. 736. Ovate seed of Milkwort {Polygala), 



with a caruncula at its base or hilum 



Fig. ISi. Seed of Asarabacca {Asaruni), with 



a caruncula on the side, called by some a raphian arillus Fig. 738. Comose 



seed of Epilobium. The tuft of hairy processes is sometimes called a chalazal 

 arillns. 



{fig. 738), where the tuft of hairs at one end of the seed is so 

 regarded. Other writers again, partially adopt these views, and 

 define the camncles as little protuberances occurring upon the 

 seed, but originating independently of the funiculus or micropyle, 

 so that the caruncles of Polygala and Euphorbia, alluded to 

 above, would come under one of the varieties of arillus, accord- 

 z3 



