Published in Botanical Museum Leaflets, Harvard University, in 1970, in volume 22, pages 297-311

Published in Botanical Museum Leaflets, Harvard University, in 1970, in volume 22, pages 313-331

Published in Botanical Museum Leaflets, Harvard University, in 1970, in volume 22, pages 333-343

Published in Botanical Museum Leaflets, Harvard University, in 1970, in volume 22, pages 345-352