AND ARILLUS. 227 



acquiring thence a light and chaffy appearance, have 

 been denominated scobiformia, whence Bergius was 

 perhaps led, very unscientifically, to call the seeds 

 of ferns ) iterally scobs or sawdust ! An elastic pouch- 

 like Arillus, serving to project the seeds with con- 

 siderable force, occurs in Oxalis, t. 762 and 1 726\ 

 In the natural order of Rutacea the same part, 

 shaped also like a pouch lining each cell of the cap- 

 sule, is very rigid or horny ; see Dictamnus albus, 

 or Fraxinella, G&rtn. t. 69, and Boronia, Tracts 

 on Nat. Hist. t. 4 7. Besides this coincidence, 

 there are many common points of affinity between 

 these plants and Oxalis, concerning colour, flavour, 

 habit, and structure. Fagonia and its allies form 

 the connecting link between them, which Gaertner 

 and Jussieu did not overlook. We have pointed 

 out this affinity in English Botany, p. 76%, and it is 

 confirmed by the curious circumstance of Jacquin's 

 Ovalis rostrata, Oxal. t. 22, having the very ap- 

 pendages to its filaments which make a peculiar 

 part of the character of Boronia. 



It is not easy to say whether the various, and fre- 

 quently elaborate, coat of the seed among the rough- 

 leaved plants, Borago, Anchusa, Lithospermum y 

 Cynoglossum.f. 201, Engl.Bot. t. 921,&c., should 

 be esteemed an Arillus or a Testa ; but the latter 

 seems most correct, each seed having only a simple 

 and very thin membranous internal skin besides. 

 Gaertner therefore justly uses the term Nut for the 

 Q2 



