Pammel — Anatomical Characters of Seeds of Leguminosae. 97 



washino^ and then staininsj with niethvlene blue. The canals 

 are simply remnants of the original cell-cavity containing 

 some plastic material. Their true nature and structure are 

 well shown by Marliere ( 1G4. pi. 1 . f. 5c.). 



Cell Contents. — In the unripe seed, asparagin commonly 

 occurs. The nucleus is made out readily, especially when 

 stained with haematoxylin. Chromatophores are more com- 

 mon in the unripe seed but frequently persist in the ripe 

 seed, as in TrifoUum, Vicia, and Phaseolus. Other proteid 

 products also occur. So long as the seed is soft, coloring 

 matter is not deposited, but when the drying process begins 

 coloring matter is deposited, in spots, as in Mucuna, Phase- 

 olus, Wistaria, or uniformly in the walls, as in Vicia, Tri- 

 foUum, Medicago, and Phaseolus. The coloring matter 

 varies in different genera and species. The general name 

 anthocyanine has been given to it. Some of the pigments 

 have received special names, as lathyrin, cytisin, and numerous 

 others. 



Tannin is always found in greater or less quantity; this is 

 most rapidly deposited during the ripening period of the seed. 

 Likiernik (149) notes the occurrence of lecithin, which was 

 first found by Schulze and Steiger (243) in the testa of some 

 leguminous seeds, and probably occurs in the Malpighian 

 cells. Likiernik obtained a second special product which he 

 has called lupeol,a substance resembling cholesterine ; from the 

 pea, phytosteriu was obtained ; from the common bean, two 

 products were obtained, paraphytosterin and phaseol. 



Light Line. — The light line, " linea lucida," " ligne lumi- 

 ere," " Lichtlinie," of various writers, is the most interest- 

 ing feature of the Malpighian cell. As a rule but a single 

 line occurs in Leguminosae, but in Gleditschia and Cassia 

 there are two. In Lespedeza, Phaseolus, and Pisum, but one. 

 Junowicz (128) gives three for Lupinus varius; Sempolowski 

 (247), two for L. angustifolius ; and Lohde (396), two for 

 Quamoclit luteola. None occurs in CJiapmannia. 



Numerous theories have been advanced as to the chemical 

 nature, physical properties, and function of the light line. 

 These views are by no means harmonious, in part because 

 writers have worked with different plants. The position 



