irregularly inserted, virgate, lateral branches ; the stem, above the stipes, 

 and branches from their base, densely beset with closely seriated whorls of 

 ramenta. Ramenta |-1 inch long, as thick as hog's-bristle, quite simple, 

 cylindrical, subacute, set in five, rarely in four, equidistant ranks, which 

 stand apart, separated by angular interspaces. Usually the ramenta are 

 quite straight and erecto-patent, but in var. ft they are incurved, and fre- 

 quently curled and entangled, and the regularly pentastichous arrangement 

 thus becomes somewhat obscured. The colour in a is a full deep-green, 

 orange at the tips, and somewhat golden on the surculus and stipes ; in ^ 

 it is usually a pale yellow-green in all parts. The substance is not very soft, 

 and in drying the frond imperfectly adheres to paper. 



This is perhaps the finest of the Austrahan Caulerpce. Our 

 figure represents one of the smaller specimens. The branches 

 are frequently numerous, and the rachis proportionally length- 

 ened. The elegantly five-, rarely four-ranked, slender ramenta 

 clearly mark the species. The only puzzling forms that occur 

 are indicated under our var. ^, and their characters seem to arise 

 from the plant being grown in shallow and sunny pools. Ex- 

 treme forms look as if they belonged to a different species, but I 

 have intermediate states connecting the smallest and most curly 

 with the typical state here figured. Dried specimens give no 

 correct idea of this beautiful plant, owing to the disappearance 

 of the peculiar five-ranked arrangement. 



Pig. 1. Caulerpa Harveyi. 2. A cross section, showing a five-ranked whorl, 

 — both of the natural size. 3. A ramentum, — magnified. 



