[1] Anna Zayaruznaya's book, The Monstrous New Art: Divided Forms in the Late Medieval Motet, presents an intriguing new perspective on a relatively small, complex, and much-scrutinized repertoire. The book is an expansion of the concept behind her important 2009 article, which portrays voice crossing in Machaut's motets as Fortune turning the tables on the usual position of voices, just as in the composer's poetry she is wont to level kings and raise the ignoble. In The Monstrous New Art, Zayaruznaya expands her purview to ars nova motets generally, and beyond voice crossing to any atypical patterning that effects (audible) divisions in a motet. For the author, "features which seem strange or unusual are places to look deeper rather than anomalies to gloss over" (20) and "the lens through which [she has] chosen to examine this repertory magnifies rifts and fissures, allegorical as well as psychological" (220). Zayaruznaya thus carves out a new subgenre of the ars nova motet that flourished in the half century between Fauvel (1310) and the 1360s, a significant bestiary comprising some twenty out of ninety extant ars nova motets (173). "Monstrous" here are those works whose text(s) treat themes of division and disunity, broadly construed to reference the character of historical people, mythological creatures (chimera, centaur, siren), allegorical figures (Fortune, Love, courtly lady, triune God), objects of piecemeal construction, and more subtly the stratified organization of "bodies" like medieval civil and clerical classes. Her vital connection is made when "motets whose upper voices dwell on a series of fragmented creatures. . . turn out to have musical forms that are equally fragmented" (62).[2] Zayaruznaya stresses that the relation between hybridity in textual subject matter and musical organization is an abstract one. Ars nova motet composers pursued what she calls the broader congruence of "form-idea relations," driven by analogy and allegory (18). Zayaruznaya situates this relationship as an "important early chapter in the history of musical hermeneutics" (234) before the more direct mimesis of Renaissance text painting.[3] The first chapter is devoted to a question upon which the acceptance of the monstrous subgenre is predicated: how can a motet have a body? Zayaruznaya finds ample evidence of this creaturely ontology. Not only do medieval bestiaries align meaning with morphology (21), "medieval music treatises are replete with body parts" (25). We are reminded of familiar analogies like Guido's hand, Grocheio's likening of the tenor to a skeleton that gives structure to the whole, the varying note heads of mensural notation, and tails [caudae] tacked on to the end of antiphons.(1) Having established a concern for taxonomy and the proper arrangement of parts, Zayaruznaya brings an eye for division to bear on musical structure, showing in the case studies that follow how composers explored and exploited the new compositional possibilities afforded by an increasingly well-ordered motet genre.(2)[4] As ars nova composers developed tenor isorhythm, an early form of intrinsically musical structure not based upon a poetic scheme (as in the formes fixes), they experimented with boundaries as a natural process in the very effort of defining them (see 222-25). Because the ars nova motet was an organic whole made up of interdependent parts, it could be conceived of as bodily. And if bodily, anything but the perfect alignment and coordination of all parts can be interpreted as deformity. Matching their potential for hybridity in form, many ars nova motets are also polytextual and speak from (or embody) three unique voices simultaneously. While the upper-voice poetry of many motets serves to amplify and interpret the classical subject of the tenor voice, it may also contradict the tenor, dividing the whole.(3) Exploiting unity as a norm in the greater quantity of non-monstrous motets, motets based upon divided materia could play with that expectation as a means of expressivity; they could distort, subvert, and otherwise comment upon wholeness. …