and issues at their extremities (or in the younger portions) where only it is 
externally visible. The primary filament has the structure of an ordinary 
Callithamnion ; its naked tips (issuing from the ultimate pinnules of the 
compound frond) are set with alternate, subbipinnate or secundly multifid 
plumules, not more than 2~3 lines in length. avelle are hidden among 
the superficial hairs, which cluster round them as involucres; they are in 
pairs, and contain many spores. etraspores secund along the inner face of 
the divisions of the plumules. Colowr a rosy red, somewhat purplish, soon 
discharged in fresh water. Swdstance soft, flaccid. In drying, the frond 
closely adheres to paper. 
This species has quite the aspect of a Péilocladia, but not the 
microscopic structure ; and notwithstanding the very copious and 
closely implicated filaments which clothe the stem and branches, 
and all parts save the ultimate ramuli, I am unwilling to sepa- 
rate it generically from Calhithamnion, in which genus various 
other Australian species of the section Dasythamnion are closely 
related to it, although perhaps it departs most widely from the 
ordinary habit of the genus. 
Though found im several places, it seems to be of rare occur- 
rence. The favelle, which were not known to me when the 
figure was prepared, are copiously found on a specimen recently 
received from Mrs. Barker. 
Fig. 1. CALLITHAMNION PLUMIGERUM,—the natural size. 2. Section through 
the spongy frond, showing the central filament and its surrounding ac- 
cessories, with the peripheric hairs. 38. Some of the hairs. 4. A pair of 
plumules. 5. One of their pinnules, with ¢e¢raspores; the latter figure 
magnified. 
