from May 1, 1830, to Aprils, 1840. 



" mense plain, offering no variety at the present season, is only 

 " occupied by Opuntias, a few stunted Prosopis dulcis, Yuccas 

 " and Berberis trifoliata, which latter, covering large tracts of land 

 " approaching San Luis, are the only flowering plants on the whole 

 " road. Near Tula the country assumes a more prosperous aspect, 

 " the hills are again covered with trees, and gradually descending, 

 " the traveller finds himself approaching the Tierra caliente. Here 

 " it was my intention to spend a few weeks for the purpose of col- 

 " lecting, and being at about the same elevation as Zaquapam, I 

 " anticipated to find a similar luxuriance of vegetation, and a good 

 " crop of Epiphytes ; but the atmosphere here, being so much drier 

 " than there, is consequently less favourable for them, and as yet I 

 " have only met with eleven kinds, which being all new will prove 

 " very acceptable to the Society. Here again I found a new species 

 " of Berberis, resembling B. aquifolium, with whitish flowers, but 

 " was not able to procure seeds of this or of the B. trifoliata." 



No. 17.— San Luis Potosi, April 19th, 1838.—" On the 10th 

 " instant I despatched from the Rancho de los Gallitos, to the care 

 " of Messrs. M'Calmont, Lyall and Co., the results of my re- 

 " searches from the neighbourhood of Santa Barbara and Valle del 

 " Maiz, consisting of two Boxes : both containing Orchidaceae, 

 " and that numbered 10, containing in addition seven sorts of Cacti 

 " and five sorts of seeds." 



These boxes detained with the five previous ones, were received 

 with them on the 27th February, 1839, in tolerably good order. 

 They contained 16 species of Crchidaceae, five kinds of Cacti, and 

 seeds of five other plants. Three of the Orchidaceous plants and 

 two Cacti are dead ; the others are now living in the Garden, but, 

 with the exception of Laelia furfuracea, have not yet flowered. Of 

 the seeds, only one kind germinated, which is supposed to be an 

 Ipomaea. 



About 170 of the plants were specially distributed on their arrival. 

 No. 18. — Bolahos, May 18///, 1838.—" About three months ago 

 vol. ii. 2nd series. 3 E 



