70 BOTANY 



sorts of vegetables : the soil is richly manured with 

 the refuse from the garrison, which unfortunately 

 makes this place very unpleasant to the olfactory 

 organs. On the uncultivated parts grow a variety of 

 beautiful plants, such as the Muscari comosum, Ero- 

 dium moschatum, Verbena officinalis, Centaurea 

 calcitrapa, &c. Later in summer these are replaced 

 by the curious Tribulus terrestris, and the not less 

 interesting Euphorbia Chamresyce. On the eastern 

 side, where the soil is more sandy, the Picridium tin- 

 gitanum is found in great abundance, as also a few 

 specimens of the Eryngium ilicifolium and Caucalis 

 maritima ; both these plants are more frequently 

 met with beyond the line of British sentries. Near a 

 damp place, about twenty yards from the middle part 

 of the vegetable-garden, may be seen a large collection 

 of Mentha Pulegium var. tomentella : no doubt this 

 plant was called by Willdenow M. Gibraltarica, from 

 seeing it grow here. Bentham, the celebrated autho- 

 rity on this tribe of plants, has shown it to be only a 

 variety of the M. Pulegium. Cichorium Intybus, or 

 divaricatum, grows here in great abundance, as also 

 Mentha rotundifolia. The vegetation on the western 

 side of this part of the isthmus presents a somewhat 

 different character ; very few plants which grow on 

 the other side are found here, whereas Euphorbia 

 Paralias, Erodium cicutarium, and Glaucium luteum 

 supply their place. The same remarkable difference 

 is observed on the real neutral-ground, beyond the 

 localities just described. On the eastern side, the 

 soil being nearly composed of sea-sand, scarcely 



