3852 The Zoologist — February, 1874. 



course in sight of visitors, because they were seeking for air. So 

 many unthinking people ascribed ray inefficient exhibition of these 

 animals to my want of skill, forgetting how many other animals 

 died from the badly aerated water in the places I have named. 



Sesarma was brought alive from the Navigator Islands to Ham- 

 burg in a slow sailing-ship. It is, as I have already named, a 

 relative of our British crab Gonoplax, which never walks out of 

 water. At first the captain of the vessel put some of his captives 

 in a vessel of water out of which they could not crawl, and the 

 water being but imperfectly aerated, the crabs soon died. So he 

 arranged a box with moist earth and sand, and in this the remaining 

 specimens burrowed, and came out occasionally, and did well. 

 I noticed, without being told by persons or books, that the surface 

 of the pterygostamian regions of the living Sesarma I had in Ger- 

 many was reticulated, or granulated, by being divided into numerous 

 small regular squares, and that these retained much water by 

 mechanical entanglement. On my telling ray friend Dr. F. Hilgen- 

 dorf, then of Haraburg and now of Yokohama, that I suspected 

 that this arrangement was to enable the crabs to carry about with 

 them their own aquaria of perfectly aiirated (because shallow) water, 

 he said it was so, and that some sharp German biologist, whose 

 name I forget, had made the discovery before I did. 



Cenobita Diogenes is a powerful West Indian land hermit-crab, 

 living in a univalve shell like our British hermits, but spending much 

 of its time out of water, entering it, I believe, only for depositing its 

 eggs. Yet it is, of course, a gill-breathing animal, needing water to 

 moisten its gills, and so enabling its blood to be purified. How 

 very small the quantity of water it needs may, however, be judged 

 when I say that the first living example I saw was given me by a 

 Swedish carpenter, who brought it from Stockholm in his jacket- 

 pocket, where he had kept it for some weeks previously as a pet. 

 The next I saw was a lot of twenty brought from the mouth of the 

 river Gibarra, in Cuba, to Hamburg in a sailing-vessel. They 

 were found walking about in the burning sun on sand which 

 was all the hotter because black. I went on board to fetch 

 them, and found them in an old cigar-box, which was wrapped 

 in a sailor's "Guernsey" to keep it warm in the hot cooking- 

 place or caboose. Some of the sailors said the crabs fed on 

 tobacco, and others that they ate potato-peel, so both of these 

 substances were placed in the box, on ojDening which the stench 



