16, Hand picking, forks, concrete pillars oyster dredges, deck screens, 

 drill dredges, drill box traps,, drill trapping, and hydraulic suction dredges have 

 been employed in the capture of oyster drills . Of these methods the hydraulic 

 suction dredge seems the most promising 



17 . A number of physical and chemical methods have been suggested and 

 others employed in the destruction and exclusion of drills and their egg capsules. 

 No ore method is applicable lr, all circumstances . Exposure of the pest on shore 

 and dumping on submerged barren muddy bottom appear to be the most inexpensive 

 methods applied to date The former method is entirely effective; the latter has 

 not been adequately tested. 



18 A number of local ecological conditions occur m various regions 

 which have proved, or may prove, useful in dull control: low salinity, areas of 

 barren mud, removal of bottom trash, and exposure on intertidal bottoms . 



19. Although Urosalpirx is considered a menace principally to oyster 

 cultuie, the presence of a limited few on bottoms supporting marketable oysters 

 may be desirable in elimination of oyster set or these oysters . 



20 Drills have probably been predators of exposed bivalves since the 

 evolution in Urosalpinx of the present drilling mechanism, and are as, or more, 

 serious predators today than, in early colonial times. There is no evidence to 

 indicate that the drill exists in greater densities per unit area today, but because 

 of its widespread distubution exists in total greater numbers, than ir. precolonial 

 times. 



ACKNOWLEDGMENTS 



lam greatly indebted to J. D. Andrews, A. F. Chestnut J. B. Engle, H. H. 

 Haskir, C. E. Lindsay, V. L. Loosanoff, I. W. Sizer, J L. McHugh, P. S.Galt- 

 soff, and L. A. Stauber for the use of unpublished data and reports without which 

 this review would have been less complete , I am especially grateful to Dr Thurlow 

 C . Nelson who first stimulated and has continued to foster my interest in the oyster 

 drill, and to Dr Leslie A. Stauber for permission to fully abstract his important 

 unpublished work on the biology and control of the drill m Delaware Bay, New Jersey, 

 which represents many years of both laboratory and field investigations . 



The following investigators have taken time to correspond with me concern- 

 ing various aspects of this review: R. T. Abbctt, J. D. Andrews, P. A. Butler, 

 A, F. Chestnut W.J. Clench, H. A Cole, J. H. Day, J. B. Engle. F. B. Flower, 

 H B. Flower PS Galtsoff, H. N. Gibbs, J. B Glancy, F Haas, D. A. Hancock, 



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