THE author of this interesting volume is well known to botanists by his valuable bibliographic work, especially his work on ferns. We have now to thank him for a welcome sketch of the naturalist of the ill-fated expedition to Arabia in 1761 to 1767, whicft was conducted at the expense of Frederick V. of Denmark.
Naturforskeren Pehr Forsskål.
Af Carl Christensen. Pp. 172. (Köbenhavn: H. Hagerup's, Forlag, 1918.) Price 8.00 krone = 9s.