INTRODUCTION. 
ii 
beautifully marked Galathea elegans, a figure of which we have given ; it is very active in 
its movements, darting backwards by sudden powerful jerks, snapping its foi e-legs quickly 
together and producing a clicking noise ; when at rest the fore-legs are extended in the 
same line as the body, perfectly straight ; when swimming, the tail is first bent under the 
body and again forcibly reflexed backwards. Near the same spot a specimen of our very 
rare Tlos muriger was dredged at a depth of ten fathoms, with other species of Crustaceans, 
chiefly belonging to the genus Philyra and Leucosia. The Tlos, like Oreophorus and 
Leucosia, is apathetic and inert, slow in its progressive movements, and relying for security 
upon its stone-like form. Arrived among the islands of the China Sea, crustaceous animals 
were observed in all their prolific variety, for in these organisms, as in others, the existence 
of a high temperature seems to increase their numerical importance, and invest them with 
more singular modifications of form and with greater brilliancy of colour. 
Two of the most remarkable Crustaceans to be met with among the group of islands 
next visited, namely, that of the Me'ia-co-shimah, are the Scopimera globosa of De Haan, and 
the Mgderis deflexifrons of the same naturalist. The former burrows in the muddy banks 
and sandflats, just above low-water mark, perforating the surface in every direction. In 
some parts of Koo-kien-san (one of this group) they are so numerous as to impart a peculiar 
colour to the shores, when seen at a distance. They walk but slowly and are very inactive 
in their habits ; when disturbed they make awkward scrambling habits to get out of sight, 
by burying themselves in the mud in the manner of certain Macr ophthalmia The latter 
genus {Mgderis), although somewhat resembling the genus Ocgpode in many particulars, yet 
differs considerably in regard to vivacity and locomotion ; like their swift-footed consimilars, 
they form superficial burrows in the sandy mudflats, into which they retreat in the same 
clumsy scrambling manner as do the Scopimera on the approach of danger. In some parts 
of the Meia-co-shimahs I have ridden over many acres of sandy mud covered with these 
bright blue crabs, and on looking behind could perceive a dark straight line made by the 
passage of the horse, as he caused them to conceal themselves in the soil in his progress 
onwards. They delight to bask at the mouth of their apertures in the sun, just after the 
receding tide has left the flats partially dry, and appear then to be most on the alert in 
procuring food. Here likewise we met with a species of Gelasimus allied to G. Chloropthalmus 
of Professor Milne Edwards, with bright orange fore-legs, the left one being bigger than its 
carapace or, indeed, than the entire body, which inhabits burrows, formed obliquely among 
