A eorreet interpretation ofthe genitive plural forms in Slavic and related Ianguages requires a detailed ehronologieal analysis o( the material. At every stage of development we have to reekon with both phonetically regular and analogieal forms. Analogy operates quite often along the same lines in different periods. Explaining an analogie change amounts to indieating a model, a motivation, and a stage of development for its effeetuation. If one of these eannot be indieated, we rnust look for a phonetie explanation.
2.The Slavie gen. pI. ending -1> points to IE *-om. It has been suggested that the ending arose from the strong reduetion of an earlier *-öm and that the origin of the quantitative alternations in the stern-final syllable which are found in the daughter languages must be sought in this development (e.g., Van Wijk 1923: 97; Stang 1957: 98). The argument eannot be maintained for ehronologieal reasons. If the reduetion was anterior to the rise of the new timbre distinetions (a -0, ete.), the quantitative alternations in the stern would be refleeted as timbre alternations in the eontemporary languages. If the reduetion was posterior to the rise of the new timbre distinetions, the timbre of the desinential vowel remains unexplained. I eonc1ude that the ending eontinues IE *-om.