﻿On the Occurrence of a Supposed Australasian Hydroicl. 79 



Thompson (1879), by Bale (1884), and by Allman (1885). 

 Our specimens do not show more than three pairs of 

 hydrothecae on any one internode, while Bale records that 

 four or even five pairs occasionally occur, nor are there 

 present branches of other than the regular pinnate order. 

 But in these respects our specimens agree with those of 

 Prof. D'Arcy W. Thompson, C.B., to whom I am indebted for 

 the opportunity of examining his fine collection. 



As to the known distribution of Sertularia elongata, so far 

 as we can learn, it has been recorded from the south coast of 

 Australia, where Bale (1884) says it is one of the most 

 common species, more particularly from Cape Wilson, Port 

 Philip, etc., in Victoria (Dr F. Miiller, cited by Thompson, 

 1879); from Tasmania (Allman, 1885), particularly from 

 Georgetown and Bass's Straits (Dr Harvey, cited by 

 Thompson, 1879); from West Australia (Allman, 1885); 

 from ISTew Zealand, where the species is less common than 

 in Australia (Gray, 1843; Hutton, 1872 ; Coughtrey, 1874), 

 particularly from Lyall Bay, Wellington (Parquhar, 1895), 

 and Kuri and Taieri beaches, Otago (Hilgendorf, 1897). 

 That is to say, the distribution is limited to Southern 

 Australasia. The West Australian locality of Allman is of 

 special interest because, while our specimens differ in detail 

 from his Tasmanian examples, they agree absolutely with 

 the West Australian form in all the points which he singles 

 out as peculiar to it. 



The trawler in whose net the present specimens were 

 found had been trawling off the Shetland Isles, and, on the 

 return journey to Aberdeen, off Buchan Ness, the last haul 

 having been taken in the neighbourhood of the " Buchan 

 Deep." Consequently, the presumption is that the specimen 

 found in the trawl-net came, if not from the last haul in the 

 " Buchan Deep," at least from some locality in the N'orth 

 Sea. It remains to account for the presence of a species, so 

 distinct and with so limited a distribution, in the North Sea. 

 Three possibilities suggest themselves — (1) that the species 

 grows in the North Sea ; (2) that the specimen was brought 

 thither attached to the bottom of a ship, as Tubularia crocea, 

 Agassiz, was, in 1895, brought from Peru to Plymouth Sound 



