PACIFIC SCIENCE, Vol. XVIII, January 1964 
32 
FEEDING HABITS: Whenever it was necessary 
to sacrifice a specimen of Haplogaster, the stom- 
ach contents were analyzed (this crab is suffi- 
ciently rare in the southern Puget Sound area 
to justify an extremely conservative use of speci- 
mens). Three animals were examined. In the 
stomach contents fragments of some species of 
brown algae were fairly common, along with 
some monofilamentous red algae, and fragments 
of what appeared to be Ulna or some other green 
algae. One animal contained a large quantity of 
single diatoms, most of these being extremely 
small. However, in the laboratory when animals 
were introduced into the tanks they immediately 
attacked barnacles attached to the rocks and fed 
on these by twisting the shell of the barnacle 
with the chelae and eventually crushing the 
barnacle. Apparently this species is omnivorous 
and feeds both by filtering, by gleaning algae 
attached to rocks, and by breaking barnacle 
shells to obtain animal tissue. It is not known 
whether or not this species captures motile 
forms. 
REPRODUCTIVE ACTIVITY: The reproductive 
activity of H. mertensii remains a mystery for 
the most part, because of its scarcity in southern 
Puget Sound waters and the difficulty of feeding 
and maintaining it under proper environmental 
conditions over long periods of time in the 
laboratory. The few data obtained are of value, 
however. With only one exception, every female 
encountered in the field during the latter part 
of November, December, January, and April 
had developing embryos attached to the pleo- 
pods (tides during February and March were 
unsuitable for obtaining Haplogaster) . Eyes 
within the egg shell became evident during the 
month of January, and hatching occurred in the 
laboratory and in the field during the middle 
part of April. Females observed during June and 
July were without eggs attached to the pleopods, 
and no further observations were made until the 
latter part of November and early part of De- 
cember, when females again carried eggs. 
PRODUCTIVITY : Three females were preserved 
and their eggs were counted. The carapace width 
and the number of eggs borne by these speci- 
mens are as follows: (1) carapace 15.6 mm, 
600 eggs; (2) carapace 18.0 mm, 2,076 eggs; 
(3) carapace 19.1 mm, 2,070 eggs. 
REFERENCES 
Baker, C. F. 1912. Notes of the Crustacea of 
Laguna Beach. First Ann. Rpt. Laguna Mar. 
Lab.: 100-117. 
Churchill, E. P., Jr. 1918. The life history of 
the blue crab. U. S. Bur. Fisheries, Bull. 36: 
99-128. 
Cleaver, F. C. 1949. Preliminary results of the 
coastal crab (Cancer ma gist er) investigation. 
Wash. State Dept, of Fisheries (49A) : 49-82. 
Drach, P. 1939. Mue et cycle d’intermue chez 
les Crustaces decapodes. Ann. de Y Inst. ; 
Oceano., NS 19(3) : 106-377. 
Garth, J. S. 1958. Brachyura of the Pacific 
Coast of America, Oxyrhyncha. Allan Han- 
cock Pac. Exped. 21(1) : i-xii, 1-499. 
Haig, J. I960. The Porcellanidae (Crustacea 
Anomura ) of the Eastern Pacific. Allan Han- 
cock Pac. Exped. 24:v-vii, 1-440. 
Hart, J. F. L. 1930. Some decapods from the 
south-eastern shores of Vancouver Island. 
Can. Field-Nat. 44(5) : 101-109. 
1933. The larval development of the 
British Columbia Brachyura, I. Xanthidae, 
Pinnotheridae (in part), and Grapsidae. 
Canad. Jour. Res. 12:411-432. 
Hay, W. P. 1905. The life history of the blue 
crab ( Callinectes sapidus ) . U. S. Bur. Fish- 
eries, Rpt. 1905:397-413. 
Hiatt, R. W. 1948. The biology of the lined 
crab Pachygrapsus crassipes Randall. Pacif. 
Sci. 2 (3): 134-213. 
Knudsen, J. W. 1958. Life cycle studies of the 
Brachyura of western North America, I. 
General culture methods and the life cycle of 
Lophopanopeus leucomanus leucomanus Lock- 
ington. Bull. So. Cal. Acad. Sci. 57(1) : 51-59. 
1959. Life cycle studies of the Brachyura 
of western North America, II. The life cycle 
of Lophopanopeus bellus hellus diegensis 
Rathbun. Bull. So. Cal. Acad. Sci. 58(2): 
57-64. 
