MARYLAND WEATHEK SEKVICE 185 



The method of diking, so much in vogue along the Bay of Fundy, 

 could be used with good effect in the low marshes, but in most cases 

 all that is needed are simple ditches extended farther inland and 

 dug deeper year by year until the system is just above low-tide mark. 

 A desirable feature of such a system is a one-way gate or valve at 

 the lower end of the ditch, for the purpose of preventing the run- 

 ning back of tide water into the ditches. Such a gate is very easy 

 of construction. 



PKAT I'.CMiS. 



Peat Bogs are characteristic of those parts of the continent which 

 show abundant signs of recent glacial action, nevertheless an 

 interesting example of a depression containing Sphagnum and a 

 society of peat bog plants occurs near Glenbumie, Anne Arundel 

 County. This area is of small extent (less than an acre) and is 

 not a typical bog inasmuch as it is not undrained but rather slowly 

 drained into a nearby stream. It derives its water from springs on 

 the adjacent banks. Plate XVI, Fig. 1, illustrates the general fea- 

 tures of this society, and shows a few of the plants, several of which 

 have not been found elsewhere in the state. Associated with the 

 Sphagnum is the characteristic bog plant Sarracenia purpurea, which 

 may be made out in the illustration, also the equally characteristic 

 Drosera rotundifolia and Drosera intermedia, Lycopodium inun- 

 datum, Eriocaulon decangular e, Xyris caroUniana, Ehexia virginica, 

 I 'Irii-tilaria vulgaris, Erioplwrum virginicum, and the common shrub 

 of northern peat bogs Chamaedaphne calyculata. At the extreme 

 left of the illustration may be seen part of a shallow pond; in this 

 were found Castalia odorala and Brasenia purpurea. In this pond 

 a thrifty colony of Marsilea quadrifolia, a native of the old world, 

 has also been established. The margin of the bog is formed by 

 Clefhra, Alnus, Decodon and a few specimens of Azalea nudiflora, 

 Magnolia virginiana, Bhus vemix, with several interesting plants of 

 herbaceous habit: Iris verna, Lilium canadense, Habenaria blephari- 

 glottis, Carex folliculata, Woodwardia areolata, Osmunda cinna- 

 iiiiinira, and Osmunda regalis. The shrub zone is followed by one 

 in which lied Maple, Black Gum and Loblolly Pine prevail.* 



*For several of the determinations I am indebted to a paper by Campbell 

 E. Waters, reported in Science N. S., vol. xxii, 1905, p. 15. 



