64 



contracted in the middle, especially those near the points of 

 the cones. The leaves are not more than six inches long, 

 the cones are about four inches long, and very regularly 

 ovate. Mr. Hartweg found it in ravines near Apulco grow- 

 ing fifty feet high. 



101. CUP RESSUS <^Mn/em (Schlechtendahl) ; 



Found near Anganguco and Tlalpuxahua, forming a tree 

 50 to 60 feet high ; 



102. JUNIPERUS ^e^ra^ona (Schlechtendahl) ; 



a beautiful shrub, with quadrangular branches and small 

 glaucous fruit, making a bush from four to five feet high, on 

 the road from Real del Monte to Chico ; 



103. JVmFERlJ S fl'accida (Schlechtendahl) ; 



a beautiful small tree from 15 to 20 feet high, with 

 weeping branches and glaucous fruit as large as a hazel 

 nut, from the neighbourhood of Regla; and 



104. JUNIPERUS mexicana (Schiede) ; 



an upright shrub or small tree, with large greenish, irre- 

 gularly oblong fruit, producing a resin like Sandarach in the 

 Real del Monte mountains ; have also been received by the 

 Society, and tlieir seeds are in the course of distribution to 

 the Fellows. 



Notes upon the Plants that produce some of the fcetid gum-resins of the 



Materia Medica. 



There is so much uncertainty in the source from which 

 the foetid gum resins are obtained, the origin of Galbanuin 

 and SagapeniLin being unknown, that of Asafcetida disputed, 

 and that of Ammoniacmn dependent upon evidence which 

 requires confirmation, that any new information upon this 

 subject is of interest. Through the kindness of the Honour- 

 able W. F. Strangways, I have been put in possession of 

 some new evidence collected in Persia by Sir John McNiell, 

 and it is so satisfactory as to deserve to be made known. 



105. Ammoniacum is certainly produced, as Professor 

 Don states, by Dorema ammoniacum, it having been found 



