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balls reached here a size up to a small clenched fist. Furthermore, 

 some few clumps were found in deep water, about 40 meters. 



St. Croix. At the shore of Great Pond on the south coast. 



St. Thomas. In the sea West of Water Island. 



Dictyosphæria Dcsne. 



In a small but very valuable note 1 ) for the understanding of 

 the classification of Dictyosphæria M me Weber van Bosse has 

 pointed out that what has hitherto been referred to D. favulosa 

 comprises 3 species, namely besides D. favulosa the two new spe- 

 cies Diet, intermedia Web. van Bosse and D. Versluysi Web. van 

 Bosse. According to the description of M me Weber van Bosse 

 D. favulosa has always a hollow thallus and lacks the peculiar 

 needles in the interior of the cells, D. Versluysi is distinguished by 

 having these and a massive thallus, and finally D. intermedia is 

 characterized by having a massive thallus in the young stage and 

 no needles. In the introduction M me Weber furthermore points 

 out that , on account of these facts , the description of D. favulosa 

 by modern authors is wrong and promises in her list of the Siboga 

 algæ later to give a description of its development and growth. 

 I regret that I have been in advance of M me Weber with my 

 examination: in excuse I may urge that 1 had nearly finished the 

 examination of my material before I became acquainted with 

 M me Weber's* note, not expecting to find so very much of 

 interest to me in it, treating as it does of Asiatic algæ. It was 

 therefore all the more interesting to find that, as far as can be 

 judged from the short diagnoses given by M me Weber, I have 

 obtained not only a form answering to D. Versluysi but very seem- 

 ingly also one coming near to D. intermedia. 



Before entering upon a description of the species found and 

 of the development of the thallus, which I have been able to fol- 

 low in D. favulosa , I must first give an account of the different 

 and contradictory interpretations found in algological literature. 



! ) Weber van Bosse, A., Note sur le genre Dictyosphaeria Dec. "Nuova 

 Notarisia", Serie XVI, 1905. 



