well and a brisk export trade developed. Liverpool was the principal receiving 

 port for Great Britain. The quantity of oysters sent each week, though not large, 

 was more than could be disposed of before the next shipment so surplusage was 

 planted in local waters to be drawn upon as required. In addition thousands of 

 barrels of younger oysters were exported to be held in English waters from one 

 to three years . Unfortunately Ingersoli makes no mention of what coastal areas 

 were utilized for holding the American oysters. Stauber (pers. com.) adds that 

 years ago (dates not given) an oyster dealer, Mr . Beach, also used to make 

 regular and extensive shipments of oysters to Eritain from waters north of New 

 Jersey. Numerous drills were undoubtedly introduced with these early shipments . 



Korringa (pers. com.) writes that it is probable that U. cinerea was first 

 introduced into English waters on a large experimental consignment of American 

 oysters in connection with the great Fisheries Exhibition in London in 1883 . These 

 oysters were relaid in east coast waters where the drill probably became estab- 

 lished. Orton (1909) notes that Crepidula fornica ta was first introduced into 

 England from America on American oysters about 1880. According to Orton and 

 Wmckworth (1928) there can be no doubt that Urosalpinx was introduced in the same 

 way and probably about the same time as_C_. fornicata . 



The earliest authentic record of the occurrence of U, cinerea in England 

 is mat of Orton (1930) who found it among animals preserved in 1920 . But Orton 

 points out that this drill was no doubt present in English waters for many years 

 and remained undetected until 1927 when experiments were being conducted with 

 native English drills (Ocenebra and Nucella ) . 



Nor is there doubt that Urosalpinx can survive the passage across the 

 Atlantic in the holds of ships. In 1939 Cole (1942) was informed that several 

 living drills had been found among American oysters received by an east coast 

 oyster merchant. He concludes that the possibility of fresh introductions of 

 drills will exist as long as American oysters are imported. The continued importa- 

 tion of the Japanese oyster drill, Tritonalia japonica, to the west coast of North 

 America on Pacific oyster seed from Japan illustrates this danger in a closely 

 related drill (Chapman & Banner, 1949). This 'danger is more acute than previously 

 anticipated. Woelke (1954) has shown 'that approximately 85% unmatched Japanese 

 drills of various stages of development in the egg case can survive shipment from 

 Japan to the United States out of water in the holds of ships among seed oysters 

 for as long as 22 days . 



According to Cole's (1942) best estimate, U. cinerea is not found outside 



of Essex and Kent, although no intensive research has been conducted for it in 

 other areas . The two main centers of distribution appear to have been Brightlingsea 



15 



