Strong tides run north with the flood, and south with the ebb, having an average rise and fall of from six to eight feet, which is very satisfactory for shore collecting. Calm sunny weather is essential for this work, as the slightest breeze tends to ruffle the surface of the water, and render the visibility poor. In this respect I was very fortunate, as we enjoyed excellent collecting weather during the whole of the second trip. The coast line consists of long stretches of beach, some composed of sand, and the others, particularly on the west coast, of banks of shells. The beaches are not of great value for collecting except for such specimens as may be cast ashore by the tides, or after gales. Rocky outcrops at intervals provide the rock pools which are necessary for littoral collecting. There are three main types of rock pools at the Chathams. (1) Those formed as deep narrow clefts in the rock. They are, for some reason, usually barren of life both vegetable and animal. (2) Those formed as shallow pools on otherwise level platforms. In these are to be found several species of crabs; sea-anemones, some of which camouflage themselves with sand and broken pieces of shells; small fishes, generally of littoral forms such as Tripterygion and Diplocrepis; starfishes of several kinds, brittle stars, molluscs and various pelagic organisms which have been left by the receding tide also occur in them. (3) The rock pools proper, which are generally of fairly large area, about four feet deep, and open to the sea either by small outlets or by the outer wall being submerged at half tide. It is essential that a pool should not be left long without a change of water, for the chemical composition, as affecting the percentage of the dissolved gases oxygen and carbon dioxide, changes rapidly to the detriment of life in the pool. The edges are generally rocky and covered with algae, sponges, and compound tunicates. The bottom is usually sandy with some rocks. A good series of pools of this kind was found at Waikawa, and another on a small island called Te Motere, just off Wharekauri, which is accessible on the shore side after half tide. The main part of my collections came from these two places. These pools contain crustaceans, tunicates, echinoderms, sponges, polychaetes, mollusca, and fishes of many kinds. In fact almost every littoral group is represented in one favourable pool. The fishing grounds at the Chathams are to be found off the outlying reefs and islets but, as portions of the coast are rocky, line fishing can be carried on with more or less success anywhere. A full account of the fishing industry is to be found in my paper published in the Journal of Science and Technology (1). The scientific results of the present expedition are arranged under the various groups. The fishes, crustacea, and tunicates will be found to be fairly complete, but in some of the other groups less detail will be noted. The reason is that it is impossible for one observer to recognise the species in every group. Further, the necessary literature is not always available. I have studied every paper procurable, and have appealed to all authorities and museums for other specimens and records from the