AN EXPERIMENTAL STUDY IN PRODUCTION AND 
COLLECTION OF SEED OYSTERS 1 
& 
By PAUL S. GALTSOFF, Ph. D., In Charge Oyster Fishery Investigations 
H. F. PRYTHERCH, Assistant Aquatic Biologist 
H. C. McMILLIN, Junior Aquatic Biologist 
United States Bureau of Fisheries 
CONTENTS 
Page 
I. Oyster cultural problems of the North 
Atlantic waters (by Paul S. Galtsoff)-- 197 
Introduction 197 
Artificial propagation of oysters. 199 
Spawning and setting of oysters 201 
Methods of spat collection 202 
Brush collectors 203 
Wire baskets 203 
Crate collectors 204 
Wire bags 204 
II. Observations and experiments in seed- 
oyster collection in Wareham River, 
Mass., 1926 (by Paul S. Galtsoff) 207 
Introduction 207 
Description of the locality 207 
Temperature of the water 209 
Salinity of the water 211 
Tides 216 
Spawning and setting of oysters 216 
Experiments with spat collectors 217 
III. Observations and experiments in seed- 
oyster collection in Onset Bay, Mass., 
1927, 1928 (by Paul S. Galtsoff and H. 
C. McMillin) 223 
Brief description of the locality 223 
Temperature of the water 224 
Salinity 226 
Page 
III. Observations, etc. — Continued. 
Tides 228 
Spawning of oysters and occurrence 
and distribution of oyster larvae. _ 231 
Experiments with spat collectors 234 
IV. Experiments in seed-oyster produc- 
tion and collection in Milford Harbor, 
Conn., 1925-1928 (by H. F. Prytherch) . 238 
Introduction 238 
Physical conditions in Milford Harbor . 239 
Temperature 241 
Salinity 242 
Hydrogen-ion concentration 244 
Tides and currents 244 
Biological observations 246 
Ripening of the gonads and 
spawning 246 
Larval period 247 
Setting 249 
Experiments in seed-oyster collection . 250 
Experiments in 1925 251 
Experiments in 1926 253 
Experiments in 1927 256 
Experiments in 1928 259 
V. Conclusions (by Paul S. Galtsoff and 
H. F. Prytherch) 260 
Bibliography 261 
I. OYSTER CULTURAL PROBLEMS OF THE NORTH ATLANTIC WATERS 
By PAUL S. GALTSOFF 
INTRODUCTION 
Of the many bottom organisms inhabiting our inshore waters, the American 
oyster occupies the most prominent place. From Cape Cod to the mouth of the 
Rio Grande it grows in great abundance in nearly every protected inlet, bay, or 
sound, forming in the localities where bottom and water conditions are favorable 
1 Submitted (or publication Apr. 15, 1930. 
197 
