108 
MR. A. O. WALKER OX A COLLECTfOX 
Surgeon-Major Archer has furnished me with the following 
memorandum on the collection, which extended over the years 
1879 to 1883 : — 
“ The species collected were for the most part obtained whilst 
dredging or searching the reefs in the neighbourhood for Mol- 
lusca. The Singapore Strait presents every variety of bottom 
within a few miles of the town— mud, gravel, sand, rock, and 
broken ground, may all be met with, each description furnishing 
its peculiar species. Most of the smaller forms w r ere obtained 
by means of the dredge at depths seldom exceeding 15 to 20 
fathoms. Some of them I extracted from living sponge and 
interstices of masses of coral. The new harbour, a narrow 
strait between the islands of Blahan Moti and Ayau Brani on 
the one side and Singapore Island itself on the other, was the 
most favourite dredging-ground, as it was conveniently situated 
and the bottom abounded in animal life. At low water I fre- 
quently waded about the reefs and shores of the numerous 
islands, and obtained many specimens under loose stones and 
lumps of coral, dead or living. 
“ The spring tides rise a full ten feet, and between the islands 
the currents are very strong, at times rendering it difficult for 
a steam-launch to make way against them. I am not aware what 
direction ocean currents, if any, take in the Strait. 
“A long sandy shore extends to JNT. of Singapore, from Tau- 
jong Bhoo to Tanjong Katong and other villages ; and at spring 
tides the water recedes a considerable distance, leaving bare ex- 
tensive banks of sand and mud, where I got a good many forms 
(amongst them two species with curved hooks on their hindmost 
claws, by means of which they hold on to a mangrove-leaf or a 
dead valve of a shell which conceals the animal from view ; these 
leaves and dead valves may be seen apparently walking along on 
the shore). [These are probably Dorippe sima and D. astuta, 
also Conclicecetes conchifera . — A. 0. W.] 
“ Brom the nets of the fishermen on this shore I also got a 
good many specimens, as likewise from the heaps of small fish, 
weed, &c., brought by the Chiuamen into the market to be sold 
as food or manure.” 
The collection is placed in the Public Museum, Liverpool, and 
duplicates of some of the new species in the Natural History 
Museum, South Kensington. 
