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mention the strange alteration in Krausse's lagoon when I last visited 

 it in January-February 1906, in comparison with its appearance 

 during my earlier visits in the years 1892 and 1896. 



Krausse's lagoon is situated on the south side of St. Croix and 

 is an alluvial formation, produced partly by material brought from 

 land by heavy showers, partly by deposits from the sea retained 

 by the mangrove vegetation. Along the south side of St. Croix, 

 and almost parallel with the coast-line at above 1 — 3 mile's distance, 

 is an almost continuous coral reef, sheltering the coast against the 

 open sea; and between the land and the reef is a rather low 

 strait of which the depth is about 2 — 3 fathoms. Under ordinary 

 conditions, even with a rather vigorous trade-wind, there is but 

 little sea, yet sufficient enough so that localities where the coast 

 looks towards the south-east, thus more exposed to the trade- 

 wind, have sandy coast with sand vegetation, whereas localities 

 looking towards the south-west and thus sheltered, have muddy 

 soil with mangrove vegetation. 



In Krausse's lagoon we have too along the south-eastern side 

 a sand dune with the vegetation common to it, sheltering the in- 

 side, low-lying lagoon. In the south-western end of the lagoon 

 the mangrove vegetation passes directly into the sea, here only 

 separated by a shorter, shallow stretcht of water, with seagrass vegeta- 

 tion and some scattered young Rhizophoras, from the mangrove 

 vegetation which fringes "Kingshill's Gut" at "Fair plane". 



On my previous journeys 1 had as earlier mentioned visited 

 Krausse's lagoon a couple of times. Seen from the land the lagoon 

 then appeared as a great number of more or less mangrove-grown 

 islands with adjacent open shallow channels or bare flats (see pi. 

 5 in my earlier paper). Especially at the eastern end these were 

 of rather wide extent, as I have mentioned in my paper (1898, 

 p. 56, pi. 8 and 9, 1900, p. 52). Along the edge landwards, at all 

 events near the plantation "Anguilla" a rather abundant mangrove 

 vegetation occurred, which I have described (1898, p. 28, 1900, 

 p. 25) in this way: "The largest lagoon on the Danish islands is 

 Krausse's lagoon, which seen at a distance from the heights inland 

 makes a splendid show with its numerous larger and smaller is- 

 lands. Here I have seen the most extensive mangrove vegetation. 

 In the neighbourhood of a little rivulet in the western part of the 

 lagoon was found a forest entirely consisting of Rhizophora, grow- 

 ing here (at least when I visited the locality in February 1892), 



15* 



