HABITS OF CRUSTACEANS. 313 



tide has left dry, you will perceive hundreds of Porcellante, 

 flattened Crabs, shuffling along the surface of the upturned 

 stones in a very ludicrous manner. They are very active 

 and bustling in their habits. This observation, however, ap- 

 plies more particularly to P.pulchripes (Adams and White) 

 and the species allied to it ; for another species, P. versi- 

 mana, (Adams and White) is found among the coral reefs of 

 Koo-kien-san, and is apathetic and indolent, and P. o&e- 

 sula (Adams and White) was dredged from twenty-four 

 fathoms in the Sooloo Sea, and was very sluggish in its 

 movements. A very rare and delicate little Crab was 

 ascertained by me to belong to the fauna of this group, 

 namely, the Mamena unguiformis of De Haan. It is 

 spider-like in its appearance, slow in its movements, and 

 lurks concealed in holes of the under-surface of stones 

 immediately below high- water mark. I discovered, also, 

 a species of Calappa, allied to C. spinocissima, under 

 stones, in the shallow sandy bays, which covers itself with 

 sand, and when captured feigns death, remaining per- 

 fectly motionless with all its members snugly tucked 

 under the carapace, and the chelae folded on the front of 

 the shell. It is a timid and slow-moving creature. 



A new species of Alphceus, a curious looking shrimp- 

 like animal, which inhabits pools under stones on sandy 

 beaches, and when disturbed makes a sharp loud clicking 

 noise, by snapping the foot-claws, likewise rewarded our 

 research. In the Padi fields, a species of Gecarcinus, 

 allied to G. laterals, is very common, running about in 

 all directions, feeding on the larvae of Dragon-flies and 

 other insects, and becoming, in its turn, the prey of the 

 large Herons that are always to be seen fishing for Frogs 



