26 
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lagoons on Laysan and Lisianski are (or were) apparently fed by abnormally 
high winter tides (Warner, 19.63) and rainfall it seems reasonable to suppose 
that the lagoon on Lisianski could have dried up during a series of mild 
winters and been refilled during a series of severe ones. This hypothesis 
* .< ‘ ■ 
could explain the description of a swampy lagoon in 1844 and no mention of 
one in 1828 or 1891. 
Hydrographic Office Chart 4, issued in August 1924, (Figure IV) 
indicates a prominent crescent-shaped ridge just inside the north and east 
0 
beaches from the northwest corner to the southeast corner. The maximum 
elevations along this ridge are 44 feet in the northern portion and 35 feet 
j ' 
in the southern section. The positions of three separate pockets of guano 
across the southern end of the island are indicated on this chart. No trees 
t 
or other prominent land marks are figured. 
Vegetation 
*'V\ V\^3- 
A summary of the vegetation of Lisianski appeared 34 years ago 
(Christophersen and Caum, 1931)- This account described the vegetation as 
opservedrlExpeditions. In 1923-192V* four 
species of plants were collected: Eragrostis , Sesuvium , Nama and Portulaca . 
Three of the species, collected by the Tanager Expedition are still found; 
E ragrostis , Nama and Portulaca . Of the 13 species recorded for the island 
in 1925 y Nicotiana and. Sesuvium are no longer found, and seven species 
recorded in 1963-64 were new records for the flora of the island. 
-A 
The earlier reports of Lisiansky (l8l4), and Walker ( 1909 ) are summarized 
in Christophersen and Caum (l93l)«‘ These indicate a well vegetated island 
which was later stripped of vegetation by introduced rabbits in the first 
decade of the twentieth century. A later work (Bryan, 1942) summarizes the 
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y 
