THE PLYMOUTH ROCK AND THE WESTERN WORLD. - These steamers, the Buffalo papers state, will be completed in time to take their place in the Michigan Central Railroad Line on the 15th of next month. The *Commercial,* speaking of them, says:
"The decorations are now all completed and ready at Mr. Wormer's rooms for immediate use. The piles of rich satin damask, made up in all imaginable variety of design; the boxes of heavy tassels and silken cords; the heaps of beautifully worked muslin, and many other such articles with which the rooms are crowded, are an earnest of the rich and tasteful style in which the boats are to be fitted up. The silver purchased in Europe by Captain Willoughby, commander of the "Plymouth Rock," has arrived, and is of the most beautiful description, both as to design and manufacture. We have never seen a collection of plate which evinced a better taste in the selection. From the massive silver salvers to the graceful candelabras, wrought with exquisite skill, every article is handsome and rich; and a table set out with such services will present a very tasteful appearance. Indeed, no expense seems to have been spared in any department, to bring the boats fully up to, if not a little in advance of, the extravagance of the day; and in proof of this we may say that some of the material for curtains in the ladies' cabin actually cost fifteen dollars and a half a yard. The fair traveler who reflects on this, will probably imagine the expenditure had better have been made for ladies dresses, but we have no doubt they will enjoy their berths all the more from the knowledge of the quality of the curtains which screen them from the public gaze. In all the decorations, Mr. Wormer has displayed that excellent taste for which he is famous, and the new boats, when completed, will form the chief attraction of the season."