rock-pools. In choosing its domicile it seems to have a decided partiality for the shell of Purpura succincta. It may often be found in the act of house-hunting, though in general choosing a shell a few sizes too large, so that there is no need to make a change until several ecdyses, or moults, have taken place. Port Jackson, Bondi, New South Wales.
29. Paguristes barbatus (Hell.).—Another of the "Hermits"; not so common nor so large as the preceding. I have found it inhabiting the shells of Purpura succincta, Monodon zebra, and Neritina punctata. Port Jackson.
30. Porcellana dispar (Stimp.).—This species frequents stones covered with mud and alga3 that are found just below low-tide mark. If one of the stones be picked up out of the water these crustaceans will not, at first, be observed, as they appear precisely similar to dirty little pieces of seaweed or mud as they slide down towards the water. Very common round the shores of Port Jackson. The carapace is about three-sixteenths of an inch in width.
Tribe Thalassinidea.
31. Callianassa sp.?—Inhabits the same localities as Mycteris longicarpus, but burrows deeper, and subsists on mud-worms. Though it is classed amongst the Podophthalmatous Crustacea, its eyes, which are reduced to mere dots, are sessile. This is not to be wondered at, inasmuch as it has very little need for eyesight, spending as it does most of its time burrowing, and but rarely coming to the surface. In colour it is of a yellowish pink, as a rule, but is sometimes white. Port Jackson; not very common. Length, 2½ in. from rostrum to telson; large cheliped, 1½ in. long.
Tribe Scyllaridea.
32. Ibacus Peronii (Leach).—The members of this species pass most of their time on a muddy bottom, in not very shallow water. They are of a beautiful salmon-colour. Length, 9 in. Rare. Port Jackson.
33. Palinurus Hugelii (Hell.).—Closely allied to the British Rock Lobster (P. vulgaris). It is the common Sydney Crawfish, and sometimes grows to the length of 24 in. Subsists on a vegetarian diet, viz. fibrous marine plants. Rocky coasts of New South Wales.
