Laudator Temporis Acti has an amusing post on ‘comical construes’. Here is another, as I heard it from one of my professors in grad school:

In Satires 1.4.120, Horace uses the phrase nabis sine cortice, “you will swim without a cork”, to express the independence of adulthood. Some years ago, a Harvard undergraduate translating the passage could not find nabis in his own little dictionary, so with admirable diligence he went to the library to check the unabridged lexica. In one or more of them he found nabus, a hapax legomenon of alleged Ethiopian origin found in the Elder Pliny (Nat. 8.69, according to the OLD). Assuming that nabis was an alternate form of this word, he combined it with the more general meaning of cortex and translated nabis sine cortice “a giraffe without a skin”. At that point, the eminent scholar teaching the class threw his book across the room and swore he would never teach undergraduates again. Of course, verb forms like nabis, where the stem is only a single letter, are hard to construe if you haven’t learned your endings.

If I ever knew the professor’s name, I have forgotten it.