Some of the most haunting and moving voices of the Pali canon are those that resonate through the fragmentary poems of the theris or nuns of early Buddhism. That these fragmentary verses have been preserved and included in the Buddhist doctrinal canon indicate that nuns were considered an intrinsic part of the sangha in the early years of Buddhism. Tessa Bartholomeusz describes the transformations and vicissitudes the order of Buddhist nuns has undergone in Sri Lanka, home of Theravada Buddhism. It is a fascinating story of transformation, innovation, and female resilience, responding necessarily to the political and social pressures of a constantly changing context. The most innovative feature of twentieth-century female asceticism was the institution of nunneries for "lay nuns," or the dasa sil matavo. The book is in two parts. Part 1 covers the period up to the twentieth century: the establishment of an order of nuns in the third century BCE, its demise, for reasons not yet known, around the 12th century CE, the Buddhist revival at the end of the nineteenth century, and the attempts to revive the lost order of nuns. One of the fine ironies of the colonial situation was that it was western theosophists and educators like Colonel Olcott who fuelled the nationalist Buddhist revival in Sri Lanka against Christianity and their western colonial counterparts; and it was a westerner, the Countess Miranda de Souza Canavarro, that Anagarika Dharmapala invited to reestablish the order of Buddhist nuns in Sri Lanka. Although the Countess's "nunnery" did not survive long, the idea of female renunciates serving the cause of Buddhism caught on, and several innovative moves resulted. By the early twentieth century, Sinhala Buddhist women had set up the institution of "lay nuns" (dasa sil matavo). These were not bhikkhunis or the female counterparts of ordained Buddhist monks, these were lay renunciates who, either as individuals or in small groups, decided to follow a life of Buddhist asceticism. The second part of the book deals with some of the organizations set up by these lay renunciates, the "nunneries" they established, their innovative methods of ordination, their dress and rules of conduct, and their perceptions of their role as "lay nuns." Most of the Sinhala lay nuns accept the fact (rigidly held by a large section of the ordained monks) that since the Theravada order of nuns died out there can never be the necessary quorum of nuns required by the vinaya rules to start the order again. However, they do not consider this an obstacle to fulfilling their roles as female renunciates. In fact, their present situation frees them from the control of monks (laid down in the vinaya rules of the canon), and gives them independence, autonomy, and a sense of power. As lay nuns or dasa sil matavo, they can evolve their own rules of conduct, create their own rituals of ordination, and yet be part of the larger tradition of Buddhist asceticism. It is in that sense a very creative and innovative form of feminine resistance, worked out within the Buddhist framework. There may be little or no consensus among the different groups of lay renunciates on many issues, such as the appropriate rituals and rites of passage for the novices, but the groups agree on the basic premise that in accordance with Buddhist doctrine, women can, if they so choose, give up their traditional social roles and adopt the life of a renunciate. Most of the lay nuns whom Bartholomeusz describes chose the life of the renunciate. Like their forbears in the Pali canon, they did so because a personal tragedy, disillusion with the world, a deep religious fervor, or a commitment to service in the cause of Buddhism led them to renounce the worldly life. Bartholomeusz also traces the shifts and changes in lay attitudes toward these renunciates. During the Buddhist revival the lay nuns had considerable support from elite social groups who were also spearheading the movement for political independence. But once independence was won, Buddhism was "restored," and the need for female participation in Buddhist activities became less politically important, elite support for the movement declined. The ideal of the female renunciate has, however, captured the imagination of women from the rural areas, and their participation has created significant changes in the movement. These renunciates are less involved in personal salvation through meditation, but -- like their counterparts, the gramavasin (village-dwelling) monks -- they believe in a life of service to their fellows, perform pujas and rituals such as chanting pirit for the laity, or engage in preaching and teaching. With the waning of elite involvement, the social standing of the lay nuns also changed. They still get a fair amount of support and respect in the villages, but without the earlier visibility and influential political support they are seen by the general public as marginalized individuals and, unlike monks, as having no special niche or status in the larger society. Yet this has not deterred women from becoming renunciates. On the contrary, Bartholomeusz records that between 1989 and 1992 their numbers increased considerably. The push to acquire ordination and recognition as bhikkunis or nuns who are members of the sangha, comes, ironically, from the foreign nuns who feel the need for such acceptance most. Bartholomeusz documents their various organizations as well as the ordination ceremonies performed, (predictably) in America. Tessa Bartholomeusz's Women Under the Bo Tree contains a fund of information for scholars and students of Buddhism. The life histories of several of the present day Sri Lankan lay nuns that she documents provide rich insights into the personalities of the individuals concerned, their contributions to the movement, and the sociopolitical and feminist implications of their institution. The reader might wish the book had leas of a textbook format where each chapter is framed by an introduction and a conclusion. However, in focusing attention on an important segment of Buddhist society -- female renunciates, who though often neglected by male historians, both lay and clerical, have yet continued to surface throughout Buddhist history -- this book serves an important function.