Also during 1893, the Bureau of Engraving and Printing competed for the postage stamp printing contract, and won it on the first try. For the postage issues of the 1894 series, the Bureau took over the plates of the 1890 small banknote series but modified them by adding triangles to the upper corners of the designs. Three new designs were needed, because the Post Office elected to add $1, $2 and $5 stamps to the series (previously, the top value of any definitive issue had been 90¢). On many of the 1894 stamps, perforations are of notably poor quality, but the Bureau would soon make technical improvements. In 1895 counterfeits of the 2¢ value were discovered, which prompted the BEP to begin printing stamps on watermarked paper for the first time in U.S. postal history. The watermarks imbedded the logo U S P S into the paper in double-lined letters. The Bureau's definitive issues of the 1890s consisted of 13 different denominations ranging from 1 cent to 5 dollars, and may be differentiated by the presence or absence of this watermark, which would appear on all U. S. Postage stamps between 1895 and 1910.[21] The final issue of 1898 altered the colors of many denominations to bring the series into conformity with the recommendations of the Universal Postal Union (an international body charged with facilitating the course of transnational mail). The aim was to ensure that in all its member nations, stamps for given classes of mail would appear in the same colors. Accordingly, U.S. 1¢ stamps (postcards) were now green and 5¢ stamps (international mail) were now blue, while 2¢ stamps remained red. (As a result, it was also necessary to replace the blue and green on higher values with other colors.) U.S. postage continued to reflect this color-coding quite strictly until the mid-1930s, continuing also in the invariable use of purple for 3¢ stamps.