391 



Art. XCVI. — Analytical Notice of the ' Transactions of the Bota- 

 nical Society.^ Vol. i. pt. ii. Edinburgh : Maclachlan, Stewart 

 &Co. ; H. Bailliere, London. 1841. 



(Continued from p. 364). 



XIII. Remarks on the Structure and Morphology of Marehantia. By 

 George Dickie, Lecturer on Botany at Aberdeen. 



The author's observations refer chiefly to Marehantia polymorpha ; 

 and they are arranged under two heads: " 1. The structure of Mar- 

 ehantia. 2. The inferences to be drawn from the facts exposed under 

 the first head." The paper is illustrated by figures. 



In the first division of his subject Mr. Dickie describes the stnic- 

 ture of the frond, and the fiructification. In speaking of the lower 

 surface of the frond he states that what is called by Sir W. J. Hooker 

 a " prominent blackish midrib," " is in reality a groove in the frond, 

 from the edges of which originate purplish scales, which, by meeting, 

 conceal the groove ; in this groove are numerous transparent fila- 

 ments." Many short radicles originate from the surface of the frond 

 at the sides of the groove. 



The receptacles of both the (so-called) male and female reproduc- 

 tive organs, are supported by peduncles ; these originate " from the 

 grooves on the lower surface of the frond, and are grooved in a si- 

 milar manner, the peduncles and their posterior grooves being conti- 

 nuous with the fi-ond and the groove on its inferior surface. In each 

 of the grooves is lodged a bundle of transparent tubular filaments, the 

 walls of which " are covered with gi-een granules, often arranged in a 

 spiral manner." The lower end of the filaments is blunt and closed, 

 the upper extremity spreads over the inferior surface of the receptacle, 

 sending off" a bundle to each lobe or ray of the former. The filaments 

 at this part " are covered with overlapping scales, similar to those of 

 the lower surface of the frond." 



What are generally considered to be male receptacles are lobed at 

 the margin, while the female receptacles are rayed ; the rays, however, 

 are stated to be " merely lobes bent upon themselves, from above 

 downwards." A perpendicular section of the male receptacle shows 

 it to consist of cellular tissue enclosed between two membranes. In 

 the tissue " are embedded numerous flask-shaped sacs, with long 

 necks, terminating each by an orifice on the upper surface of the re- 

 ceptacle. * * The sacs contain the bodies called anthers, 



