114 Alexander W. Evans, 



sis, 9, page 419, and 10, p. 38) ; Eden Harbor, collector not named 

 (M.) ; Cockle Cove, Coppinger (M.). 



The following additional stations may be cited from the litera- 

 ture: Basket, Burnst and Staten Islands and Beagle Channel, 

 Spegaszini (16, p. 256, including the type material) ; Otway Bay, 

 Puerto Bono and Desolation Island, Savatier (2, p. 245) Tuesday 

 Bay, Naumann (19, p. 40, as Pseudoneura fuegiensis) ; Newton 

 Island, Diiscn (28, p. 18, as Aneura fuegiensis) ; Hale and Atalaya 

 Islands and Canal Inocentes, Skottsbcrg (32, p. y, and 22, p. 49, 

 as A. fuegiensis). 



There are few species of Riccardia that rival R. fuegiensis in 

 size and complexity, and the thallus presents the unique feature of 

 developing acropetal appendicular organs in the form of longitu- 

 dinal lamellae on the ventral surface. These are described and 

 figured not only by Massalongo but also by Goebel (11, p. 280, 

 /. J"7p), who attributes to them the function of holding water by 

 capillarity. Schiffner's figure (under Pseudoneura) may like- 

 wise be consulted. The color of the species varies from pale to 

 dark brown, portions of the thallus sometimes becoming almost 

 black. The plants are prostrate and either form loose depressed 

 mats or else creep over the surface of other bryophytes. Neither 

 rhizoids nor stolons have been observed. 



The axis is clearly differentiated and grows indefinitely, the 

 living portion being often 6-8 cm. long and occasionally as much 

 as 12 cm. The width is mostly 1-1.5 mm. and the thickness 

 0.3-0.35 mm. In the axis a broad thickened median portion and 

 unistratose wings can be distinguished, the change from the one to 

 the other being fairly abrupt. The median portion is plane or 

 nearly so dorsally and convex ventrally, the thickest part being 

 mostly twelve to sixteen cells across. The cells of the superficial 

 layer are small and almost isodiametric, averaging about 25 x 22 /*; 

 their walls are somewhat thickened but pale. All the interior cells 

 are elongated and average about 30 /x in diameter. The two or 

 three layers just within the surface layer have strongly thickened 

 and often pigmented walls, thus forming a fairly distinct sclerotic 

 zone ; this passes gradually into the central core, which is composed 

 of cells with thinner and paler walls, but even here the walls paral- 

 lel with the surface are usually distinctly thickened. The ventral 

 lamellae are in about twelve rows on a well-developed axis. They 



