sparingly and very irregularly branched, and everywhere densely clothed 

 with minute papillseform ramenta. The branches are remarkably erect, and 

 their summits frequently stand at a level, giving a corymbose character to 

 the frond ; they are alternate, or opposite, or secund, and are occasionally 

 binate. In var. /3 the ramenta are much larger than in the ordinary form, 

 more swollen and more loosely set, but they are of the usual elliptical form, 

 and intermediate states are found. The colouf is a pale-green in var. a ; and 

 a much fuller and darker green in |3. The mbatance of both is firm, be- 

 coming rigid when dry, in which state the frond does not adhere to paper. 



This plant varies but little in its ramification, but, at different 

 depths of water, it varies greatly in its diameter, and in the 

 closeness or laxity and the size of the oval ramenta that cover 

 its branches. When growing in shallow tide-pools, near the 

 summit of the reef, it is greatly dwarfed, but not otherwise 

 changed. The slender varieties are from deep water. The var. 

 ^, which I had at one time felt disposed to separate specifically, 

 grew in deep tide-pools near low-water mark, and was of so 

 much more brilliant colour and more lubricous substance than 

 var. a, and had such large ramenta, that, when growing, it 

 looked very different. Afterwards I found some intermediate 

 specimens that connected it with the normal form. 



Though common in many places along the west and south 

 coasts of Australia, C. swipliciuscula has, until very recently, 

 been only known to most botanists by Turner's figure and de- 

 scription. 



Fig. 1. Caulerpa simpliciuscula, the normal form, — natural size. 2. One 

 of its ramenta, — mngmjud. 3. Var. (3. vesiculifeka, — tlie natural size. 

 4. One of its ramenta, — magnified to the same scale as Jig. 2. 



