LONDON, May 30. - The Americuns were unusually fortúnate in the betting on the Derby. Richard Croker won on the flrst race lv baoking Cuurtier, tha Prince af Wales encry. Croker backed Courtier simply becauáe he had heard that the Prince of Wales backed one of the Croker horses at Nevvmarket. Croker, however, lost nis winning on Courtier by buuking The Owl for the Derby. Josoph H. Manley presentod a letter of iutroUuction from the late secretary of state, Walter Q. Gresham, to Lord Rosoberry on Monday last. The premier received him most cordially. Chlefly owing to this Manley selected Sir Visto to win the Derby, and won enough to pay a large purtion of the expenses of his European tour. Probably the most fortúnate of the Americans w s UxiKird, the sugar milliouaire ' of Nobraska. Ho ?.'iid: "I had the samo bellet in Lord Boseberry's luck th.at I had in Pro.-iiúunl !--" Völuad's luck; neiice I backod S.r Visto." Rjpresentative Salí, óï Massáoiiusetts, bácked Curzon lor a place. He selected Ctirzon owing to ths marriage of tha Rt. Hon. George N. Curiou and Miss Mary Leiter.