In the Flora of tropical Asia a very important position is occupied by the Laurel family. Several species of this family deserve to be particularized on account of their commercial value: thus, from the _Laurus camphora_ comes the camphor most esteemed by British physicians, while the aromatic rinds of the _Laurus cinnamomum_, _Culilawan_, _Malabathrum_, and _Cassia_, constitute the various kinds of cinnamon. The _Laurus cassia_ is not to be confounded with another Indian tree, one of the Leguminosæ, the _Cassia fistula_, whose enormous cods formerly played an important rôle under the name of Cassia in therapeutic science. While speaking of trees which produce aromatic substances, I must not forget to mention the _Styrax benzoïn_, and the _Boswellia serrata_. The former is a member of the family _Styracaceæ_, whose trees or shrubs, chiefly tropical, are known by their monopetalous flowers, their epipetalous stamens, their long radicle, leafy cotyledons, and by a part at least of the ovules being suspended. The _Styrax benzoïn_, a native of the Indian islands, yields the resin called benzoin. The juice exudes from incisions made in the bark, and when dried, is removed by a knife or chisel. Each tree yields about three pounds' weight annually, the gum formed during the first three years being superior in quality to that which subsequently exudes. It is largely employed by perfumers, and in medicine is esteemed a remedy for chronic pulmonary disorders. _Styrax officinale_, a native of the Levant, furnishes the balsamic resinous substance known as storax, which is also one of the materials manipulated by perfumers, and in medicine is used as a stimulating expectorant. The _Boswellia serrata_ supplies the fragrant incense whose vapours were anciently supposed to be peculiarly agreeable to the gods made by man's hands or conceived by his imagination.