170 PROF. W. J. DAKIN : EXPEDITION TO THE 



on this island, but they prefer the ground just below the bushes. They are 

 more timid than the Noddy Terns, and leave their nests on the approach of 

 an intruder. 



Mention has already been made of the Lesser Noddy which inhabits the 

 mangrove trees of Wooded Island and the islet to the north of it. In the 

 case of the latter, the mangrove thicket presents a curious appearance at the 

 breeding season. The branches of the trees are covered with picturesque 

 nests of seaweed, the straggling ends of which hang down ; the birds are 

 not at all shy, as may be guessed from the photograph (see PI. 11). 



Reptiles are much less common in the Easter Group than on the islands of 

 the Wallaby Group, and no snakes are found. Two small species of lizards 

 were seen on Rat Island but not captured. Rat Island was one of the few 

 places where we were troubled with Diptera — another relic of human 

 occupation. 



The reef-flat surrounding Rat Island did not prove to be a very good 

 collecting ground. Vermetus was common as usual, and rock pools con- 

 taining small fish and some crabs and Macrura were abundant. A living 

 specimen of Physalia was captured in one of them, having drifted in with 

 the previous high tide. Corals and gorgonids occurred on the submerged 

 blocks of the little jetty which runs out for a few yards on the north of the 

 island. Wooded Island coral flats — both the lagoon and seaward flats — ■ 

 proved extremely interesting, and were the home of a rich shore fauna. The 

 margin of the lagoon flat, which as we have already pointed out presents an 

 almost vertical or overhanging wall dropping to about 10 fathoms of water, 

 is a beautiful picture of coral growth, a considerable number of species 

 occurring side by side. A very large GVinoid lives in enormous numbers 

 amongst these coral growths, and in many cases half a dozen or so could be 

 picked up in a mass. Their colour was a gorgeous mixture of green and 

 yellow, but unfortunately it left the animal's body with the greatest ease on 

 preservation, and coloured everything else a rather dirty brownish green ! 



Another animal which was extraordinarily abundant on this little stretch 

 of lagoon flat (only on the margin) was a large and beautiful Nudibranch, 

 almost certainly new and allied probabl)' to Dendronotus. The singularity 

 of its occurrence is accentuated by the fact that notwithstanding its abun- 

 dance here, not a specimen was captured anywhere else at the Abrolhos, and 

 on our second visit in 1915 it was just as common at this place as two years 

 before. 



Large simple Ascidians and a large species of Serpulidse were marked 

 features of this reef-margin. On the seaward side several species of 

 Chitonidas were obtained, Cryfrtojilax sp. being fairly common. Sea- 

 Urchins (chiefly Eeldnometra mathce) occur in large numbers, each 

 individual in a little hollow in the reef-flat which it has excavated and 

 into which it fits. Nudibranchs and Tectibranchs (Aplysia sp.) were 



