rort] CURRENT LITERATURE 77 
amount of evidence presented leaves no doubt as to the correctness of the 
conclusions. Aside from having solved one of the most obscure problems 
of plant pathology, the authors have shown that it has a more general bearing 
in showing that these plant galls, due to bacteria, present many analogies to 
animal tumors. The successful isolation of causal bacteria from the plant 
tumors, after many failures, leads one to hope that the work will stimulate 
renewed search for organisms in animal tumors.—H. HASsELBRING. 
Coastal floras —H. CHERMEZON™ has recently made a contribution to the 
study of coastal floras. In the introduction he calls attention to the well 
known peculiarity of these floras, the interest they have excited in botanists 
since ancient times, and the theories advanced as to the relation between them 
and salt in the soil. 
The main part of the work is divided into three sections. In part 1 is 
given a description of the structure of the leaf and stem of a large number of 
plants of the coast, chiefly of France, but also of some of the salt-desert 
regions of Tunis. In part 2 a study is made of the characters peculiar to 
plants of the coast. There are three categories of habitat: (1) the region of 
sands, including (a) beaches and (6) dunes; (2) region of rocks and cliffs, 
including (@) rocks and bowlders exposed to the spray and (0) the top of cliffs; 
(3) damp salty places including (a2) muddy flats and salt marshes (the halo- 
phytic zone par excellence), and (6) damp prairies, not reached by the sea, 
which form a transition to the flora of the interior. 
Part 3 is devoted to a discussion of the flora. It is divided into two parts: 
(x) marshes, rocks, and beaches; and (2) dunes and sands. The transition 
between the two is made by the plants of the beaches which have characters 
common to both. In the first group succulency and development of water- 
tissues are the striking features, while the second shows more often thickening 
of the cuticle, sinking of stomata, and abundance of hairs. As the stations 
of the first group are the most salty, while the dunes are not salty at all, the 
author distinguishes two sorts of floras, the halophilous and the xerophilous. 
The xerophilous flora reaches its maximum in the dunes, where the characters 
are such as are met with in other xerophilous floras; but it is less specialized 
than that of the desert or even the Mediterranean flora, since the dryness is 
less pronounced and less continuous. The halophilous flora occupies the 
beaches, the rocks and bowlders, and the salt marshes. The beach and the 
dunes are not distinct, plants passing from one to the other; but a great many 
sand-loving plants of the dunes are absent from the beach, which the author 
explains by the presence of salt, small in amount but sufficient to eliminate 
them. The rocks and bowlders in the vicinity of the sea, exposed to the spray, 
are occupied by a flora with special characters, less halophilous than those of 
“4 CHERMEZON, H., Recherches — sur les aie littorales. Ann. 
Sci. Nat. Bot. 12:117-313. figs. 52. 19 
