be regarded as an abortive plumule. It is more correct, therefore, to de- 

 scribe the plumules as being alternately dissimilar ; one of each pair alter- 

 nately reduced to a ramulus, the other elongate. The elongate plumule is 

 about the tenth of an inch in length, slightly incurved, and regularly, 

 oppositely bipinnate. The articulations of its rachis are cylindrical, and 

 three to four times longer than broad ; its ovate pinnse are so closely pinnu- 

 lated that the parallel pinnules touch each other through almost their whole 

 length, and the pinna looks like a leaflet. The articulations of the pinnules 

 are about as long as broad, and quadrate. Tetraspores are borne on the 

 stuppose fibres of stem and branches. Favella, surrounded by numerous 

 inrolled, elongate, branched, involucral ramuli, are borne on shortened 

 branches. The colour is a deep, dark brownish-red, fading, on exposure, 

 to dull olive-green or yellowish-white. The substance is rigid, and the 

 plant scarcely adheres to paper in drying. 



When, half in sport and half "honoris causa''' I gave the 

 name of a dear friend to the new species of Ballia here figured, 

 I little anticipated that before I should have an opportunity of 

 publishing this figure, he to whom it is dedicated would have 

 been numbered with the dead. Those who knew the late Robert 

 Ball, LL.D. (and what British naturalist does not know him, at 

 least by fame ?), will not wonder that his intimate friends should 

 cherish his memory as one of the fondest recollections of their 

 past lives. To me his loss is greater than to most others, for he 

 was one of my earliest scientific friends and instructors, and for 

 thirty-two years our friendship was unbroken. 



The genus Ballia was founded in 1840, in honour of Dr. 

 Ball's sister, and now includes at least four well-marked species, 

 all natives of the southern hemisphere. B. callitricha, Ag. {B. 

 Brunonis, Harv.), the first named species, is widely dispersed; 

 the others are more local. 



Fig. 1. Ballia Kobertiana, — the natural size. 2. Two pairs of opposite, 

 " alternately unequal " plumules. 3. A pinna, from one of the major plu- 

 mules. 4. An involucre containing a favella. 5. The favella, removed. 

 6. Spores from the same : — the latter figures more or less magnified. 



