STRUCTURE.] MODIFICATIONS OF ANTHER. 343 



vascular tissue, which diverges on each side from the filament, 

 and passes through that part of the anther from which the 

 pollen has been incorrectly supposed to separate, and which 

 is called the receptacle of the pollen by some, the trophopollen 

 by Turpin, and the raphe by Link, but with greater propriety 

 the septum of the anther. Its coat is called by Purkinje 

 exothecium. 



In the most common state of the anther the cells are 

 parallel with each other (Plate III. fig. 14.), and open with 

 two valves (Plate III. fig. 13. ), by a longitudinal fissure 

 from the base to the apex ; in Labiates and Figworts (Scro- 

 phulariacese) the cells diverge more or less at the base 

 (Plate III. fig. 15. 18.), so as in some cases to assume the 

 appearance of a one-celled horizontal anther, especially after 

 they have burst. In Cucurbits the lobes are very long and 

 narrow, sinuous, and folded back upon themselves (Plate III. 

 fig. 24.). In Salvia the connective divides into two unequal 

 portions, one of which supports a cell and the other is cell- 

 less ; in this case the connective has been called by Richard, 

 distractile. Lacistema (Plate IV. fig. 7.) affords another 

 instance of a divided connective. In many of the cases of 

 excessive divergence of the cells the line of dehiscence of the 

 anther is changed from longitudinal to vertical (Plate III. 

 fig. 20. 17.), and has actually been supposed to be really 

 transverse ; an error which in most cases has arisen from not 

 understanding the real structure of the anther. Some 

 anthers, however, no doubt have cells that burst transversely, 

 as Lemna, Alchemilla arvensis, Securinega, &c. (See Plate III. 

 fig. 12. 16. 30.) 



All anthers are not two-celled, their internal structure 

 being subject to several modifications. It sometimes happens 

 that the anther is four-celled, as in Tetratheca. In Epacris 

 the two ordinary cells become confluent into one, and the 

 anther is therefore one-celled. In Maranta and Canna only 

 one cell is produced, the other being entirely suppressed. In 

 most Amarants, Epacrids, and some other plants, the anther 

 seems to be absolutely one-celled. (Plate IV. fig. 8.) 



Of all these the four-celled anther is the type, and both 

 the one-celled and two-celled are probably mere modifications 



