*contains 4x Fast-Attack Transport (APD), 2x High-speed Minesweeper (DMS), 2x Seaplane Tender (AVD), and 1x Destroyer Minelayer (DM)
Clemson-class destroyers (along with the preceding Wickes-class) were the most numerous class of destroyers the US Navy had during/before WWII. More than 30 of these destroyers were converted as Fast-Attack Transports: the number of stacks were reduced to 2, all torpedo tubes removed, and on some the 4"/50 guns were replaced with 3"/50. Four landing crafts (either LCVP, LCP(L) or LCP(R)) on davits were fitted amidships.
Some ships of the class were converted to Childs-class Seaplane Tenders (AVP, later AVD) to service the navy's long-range patrol boats (like the PBY Catalina), foregoing the torpedo weaponry and replacing them with aviation fuel tanks.
Other ships were converted into High-Speed Minesweepers (DMS) with DD117 Dorsey becoming the class-leader (DMS1). Various reels are located amidships for the paravanes, as well as launching cranes at the fantail.
Eight destroyers (4 Wickes + 4 Clemson) were converted as Destroyer Minelayers (DM) lead by Wickes-class Gamble (DM15; ex-DD123) and Clemson-class Preble (DM20; ex-DD345). This was done by removing all the torpedo tubes and installing mine rails instead.
http://en.wikipedia.org/wiki/Wickes-class_destroyer
http://en.wikipedia.org/wiki/Clemson-class_destroyer