323 VEGETATION 



Salt-MxVesi-i Formation. — Near the foot of the north slope of the Blue 

 Hills and directly south of Nassau, the Low coppice is interrupted by a large 

 tract of marshy land in the center of which is a considerable pond of water. 

 This rises and falls with the tides and is almost as salty as the sea itself. The 

 soil consists of honeycombed rocks, with edges so sharp that walking is diffi- 

 cult. Within the innumerable crevices there is a deposit of soft, sticlcy, white 

 ooze, described in the chapter on Soils of the Bahama Islands as "brackish 

 swamp marl," which to all appearances is as barren as the rock itself. On the 

 edges of the pond this ooze completely covers the rock, and the conditions for 

 plant growth are here so unfavorable that only the extremely Tesista.nt Aster 

 iennuifolius L. and Distichlis maritima Eaf. have gained a footing. Both of 

 these species have long rhizomes running an inch or two under the surface 

 and sending up aerial shoots at the nodes. They cover the soil rather closely 

 in places, but are absent in others. Behind these where the honeycombed rock 

 is exposed is an exceedingly dwarfed and prostrate growth of Conocarpus 

 erecia sericea Pors. and Rhacicallis maritima (Jacq.) Schum. Their gnarled 

 and contorted stems run like snakes among the knife-like edges of the rocks. 

 But in spite of all discouragements, these plants were bearing fruit, even 

 when less than 6 inches in height. Even here the parasitic Cassytha was 

 running along the rock from plant to plant and attacking everything in its 

 way. Further from the margin of the water other low scrubs began to appear, 

 still much dwarfed, but not so prostrate. Among these were Torriibia longi- 

 folia (Heimerl) Britton (Blolly), Bumelia microphylla Griseb. (Ink-berry), 

 Jacquinia heyense Mez. (Joe-bush), and Mimusops sieberi -K. DC. (Wild sapo- 

 dilla). The two grasses, Uniola paniculata L. and Uniola racemiflora Trin., 

 also found a place here, and several species of Tillandsia attached themselves 

 to the shrubbery, even in the most exposed situations (Plate XL, Pig. 3). On 

 the eastern end of the marsh, where conditions were more favorable to growth, 

 the Conocarpus reaches 15 feet in height, and Iva cheiranthifolia Kunth, and 

 Cladium effusum (Sw.) Torr. appear in considerable abundance. Near the 

 outer edges of the marsh the Ooccothrinax jucunda Sarg. (Silver-thatch palm) 

 forms a conspicuous fringe and at about this point the ordinary low coppice 

 growth comes in. 



The vegetation of the fresh marshes that extend for some distance along 

 the north shore just behind the beach to the west of Nassau, is very similar to 

 what has been already described for similar situations on the south side, but 

 some plants were common here that were not found on that side. Among 



