INTRODUCTION. 
Vll 
found running over the rocks near the sea, feeding on the Blennies and Periopithalmi that 
quit the water occasionally ; they feed also on the different Cirripedes. There is one species 
(G. latifrons, White) that I have found inhabiting fresh- water rivulets and ponds, which, 
however, has all the quick and wary habits of the other species, and when pursued hides 
under weeds and stones. Among numerous other forms observed along the Bornean coast, 
I may allude to the Sicyonia of Edwards, which swims in a slow and deliberate manner 
forwards, and occasionally propels itself backwards with a sudden jerk ; it keeps at a con- 
siderable distance from the shore, and appears to love deep still water. 
The Spier oma are generally obtained in company with Cymodocea, Cypridina, Amphi- 
podea, and others, among dense masses of floating sea-weeds, where they appear to lead an 
active predatory life amid the populous mazes of the Sargassum, &c. They are constantly 
spinning and darting about, rolling up their bodies into a ball, then straightening them, and 
crawling among the algae and keratophytes, with a great deal of vivacity. Among the 
collection brought home in the Samarang, are several species not before known to Crusta- 
ceologists. Like the genera Thenus and Ibacus, the Scyllarus lives at some distance from 
the shore, and in tolerably deep water. It swims in the manner of Crangon, by rapid 
inflexions of the abdomen, occasionally springing through the water with the greatest 
velocity in a backward direction, and, when caught, wounds the hands with its tail, throwing 
it about with violent jerks. At Unsang in Borneo, which was the next place visited, I 
discovered a new species of Hope, (White,) an active restless Crustacean, darting and whirling 
forwards and backwards, and frequently producing a loud clicking noise by snapping the 
claws of their fore-legs, in the manner of Callianassa and Squilla. Specimens were found 
under nearly every stone which I turned on the beach at low water. The Gonodactyli 
appear to differ slightly from the Squilla in their habits, inasmuch as they are generally 
found in deeper water, whereas the Squilla affect the shallow, weedy, and sandy bottoms, 
within coral-reefs and on flat beaches, where they hide in holes of the banks of pools, across 
which they dart occasionally in straight lines, leaving a turbid track behind them. Both 
genera have, however, the same power of producing a loud clicking noise with the claws of 
their fore-legs, and of inflicting very severe wounds with their chelae, using them in a 
scytlie-like manner, like the Mantis which they resemble. The Trapezia are tolerably lively 
in their habits, with the same manner of hiding and shuffling under stones as the PorceUana , 
but unlike them they inhabit the coral branches and madrepores of deep sunken reefs. 
