60 
Algae of Tasmania. 
as a sparrow’s quill, cylindrical, cartilaginous, about a quarter of 
an inch in length, expanding thence, from a cuneate thickened 
apex, into a frond 4-12 inches long or probably more, which 
divides in an irregularly dichotomous manner into a few principal 
segments which preserve a nearly equal breadth of from 1-2 lines 
(in different specimens), and produce along their margins in a 
manner sometimes alternately pinnate, sometimes alternately gemi¬ 
nate secund, or imperfectly dichotomous, lesser distichous seg¬ 
ments half the breadth of those from which they spring, which 
either at once divide into dicliotomously muldfid ramuli gradually 
narrower, or are themselves pinnated with such raultifid ramuli. 
These multifid ramuli, and even the major segments, preserve a 
tolerably defined flabellate outline.—-Such is the common state of 
the more regular specimens, but others occur which are cleft in a 
manner so exceedingly irregular, between pinnate and dichoto¬ 
mous, that it is impossible to convey in words any idea of the 
branching. One character, however, runs through all the varie¬ 
ties, namely: every axil, from the greatest to the least, is remark¬ 
ably rounded and large; and in the more finely divided or upper 
part of the frond, the segments overlap each other above the 
axils, leaving wide circular spaces like holes in a net. The apices 
are all acute; the ultimate ramuli even subulate, from which cir¬ 
cumstance, added to the colour, the position of the fruit, and the 
internal structure of the frond, I am induced to place this plant 
in the restricted genus Sphaerococcus (Grev.) rather than in Rho- 
domenia, although there is no trace of midrib. The internal struc¬ 
ture to which I allude consists in a number of large intercellular 
spaces of a roundish figure that exist throughout the substance of 
the frond, and give a transverse section of it a honey-combed 
appearance; while under a pocket lens they impart a netted cha¬ 
racter to the surface of the frond. These air-cells separate the 
two opposite surfaces so considerably, that we must call the frond 
rather very much compressed than truly flat. The coccidia are 
borne only on the ultimate divisions, and generally at or near the 
apices. At first they are conical, they afterwards become more 
globose, and finally are tuberculated and very irregular in form. 
They arc of a fleshy substance, and contain a favella, or mass of 
