Page:The American Cyclopædia (1879) Volume X.djvu/414

 408 LICHENS the range of the common law jurisdiction. The general rule then, in the United States as well as in England, respecting licenses which con- cern the enjoyment of interests in lands, main- tains their revocability, no matter what may have been done in reliance upon them ; and no matter whether the question arise between the original parties, or be complicated by convey- ance to third persons. In international law, licenses are permissions to carry on a trade in- terdicted during war. The power to grant them rests naturally with the sovereign ; but in time of actual hostilities they may be im- mediately issued by generals or other high mil- itary or naval officers. These licenses are lib- erally construed, but no advantage must be taken of the indulgence which they grant ; as for example, by carrying a different kind of goods from that expressly permitted, or by changing, without the consent of the granting power, the person by whom the license was to be used ; for, if it be not expressly transfer- able, the license is personal only. In Ameri- can constitutional law questions of conflict between state and federal authority sometimes arise in regard to licenses, but they are not often difficult of solution. Thus, it is clear that a license granted by federal authority, within the sphere of congressional power, must be paramount to any state law or state regula- tion ; while, on the other hand, a state license to do what would conflict with any federal authority must be void. This subject received thorough examination in the case of Gibbons v. Ogden, 9 Wheaton's Reports, 1, in which a law of New York giving exclusive privileges in the public waters of that state was held void as conflicting with the power of congress over commerce. But when a license fee is imposed by federal authority for revenue pur- poses only, being but a tax, it interferes with nothing allowed or prohibited under state laws. Thus, liquor dealers are now required to pay a federal license tax ; but this does not license the sale of liquors in any state where it is forbidden, or relieve from any state re- quirement of license or other state regulation. It gives no permission to carry on the busi- ness, but taxes it if carried on. (License Tax Oases, 5 Wallace, 462.) LICHENS. In the classification of plants we have the two great sub-kingdoms of flowering and flowerless plants ; the flowerless or cryp- togamous plants are subdivided into acrogens, which are mostly herbaceous, with a distinct axis of growth, having foliaceous appendages and growing from the apex, and thallogens, which are seldom herbaceous or with folia- ceous appendages, the growth taking place periphically or horizontally. To the thallogens belong the alg, the fungi, and the lichens. These orders are usually readily distinguished. But there are some lichens which approach algae, and others so near fungi as to make their classification difficult without careful study. The vegetative portion of a lichen is the ihallus, which may be regarded as the plant proper, as it performs all the functions of root, stem, FIG. 1. Tree Lungwort (Sticta pulmonacea). and leaves ; it is exceedingly variable in form, texture, and color. When the thallus forms a flat expansion it is called foliaceous, as in sticta (fig. 1); if erect and cylindrical, as in cla- donia (fig. 2), it is fruticulose; in some it forms a mere crust on the soil or other surface, when it is called crusta- ceous; and when concealed beneath the fibres of the bark of trees, it is hypophleous. Whatever the form of the thallus, it consists wholly of cellular tissue, and its surface is destitute of stomata. (See LEAF.) The struc- ture of the thallus is not homogeneous, but cl V""- Fio. 2. Cladonia coccinia. FIG. 3. Microscopic View of Transverse Section of the Thal- lus of a Lichen, c I, the cortical layer; g, gonidia; m I, medullary layer ; ?i, the lower layer or hypothallus. the microscope shows several distinct layers. A magnified cross section, as given in fig. 3,