Have a silver tongue? This month's mini-Annals of Improbable Research announces a limerick contest brought to you by lumpers, splitters, and nosology. "To the extent that he pulls together the multiple features of single gene syndromes, the medical geneticist is a lumper. To the extent by various means that he identifies heterogeneity, he is a splitter," writes Victor McKusick in the 1969 paper that is the inspiration for the contest.