CORTEX PRUNI SEROTIN^. 253 



rather larger and more elongated, and having a thicker skin ; also in 

 the stone being flatter, narrower, pointed at either end, with the 

 ventral suture much more strongly curved than the dorsal. The 

 fruits seem rather more prone to become covered with a saccharine 

 efflorescence. 



CORTEX PRUNI SEROTIN^. 



Cortex Pruni Virginiance ; Wild Black Cherry Bark. 



Botanical Origin — Prunus serothui Ehrhart (P. virginiana 

 Miller non Linn., Cerasics serotina DC.) — ^A shrub or tree, in favour- 

 able situations growing to a height of 60 feet, distributed over an 

 immense extent of North America. It is found throughout Canada as 

 far as 62° N. lat., and from Newfoundland and Hudson's Bay in the 

 east, to the valleys west of the Rocky Mountains.^ It is also common 

 in the United States. 



The tree is often confounded with P. virginiaTia L., from which, 

 indeed, it seems to be separated by no fixed character, though American 

 botanists hold the two plants as distinct. It is also nearly allied to the 

 well-known P. Padua L. of Europe, the bark of which had formerly a 

 place in the Materia !Medica. 



History — Experiments on the medicinal value of Wild Cherry Bark 

 were made in America about the end of the last century, at which time 

 the drug was supposed to be useful in intermittent fevers.^ The bark 

 was introduced into the United. States Phai'Tiiacopoeia in 1820. An 

 elaborate article by Bentley' published in 1863 contributed to bring it 

 into notice in this country, but it is still much more employed in 

 America than with us. 



Description — The inner bark of the root or branches is said to be 

 the most suitable for medicinal use. That which we have seen is 

 evidently from the latter ; it is in flattish or channelled pieces, ^ to -^ 

 of an inch in thickness, | an inch to 2 inches broad, and seldom ex- 

 ceeding 5 inches in length. From many of the pieces, the outer suberous 

 coat has been shaved off, in which case the whole bark is of a deep 

 cinnamon brown; in others the corky layer remains, exhibiting a 

 polished satiny surface, marked with long transverse scars. The inner 

 surface is finely striated, or minutely fissured and reticulated. The 

 bark breaks easily with a short granular fracture ; it is nearly without 

 smell, but if reduced to coarse powder and wetted with water it evolves 

 a pleasant odour of bitter almonds. It has a decided but transient 

 bitter taste. 



The bark freshly cut from the stem is quite white, and has a strong 

 odour of bitter almonds and hydrocyanic acid. 



^croscopic Structure — The chief mass of the tissue is made up of 

 hard, thick-walled, white cells, the groups of which are separated by a 



* Hooker, Flora Boreali- Americana, i. tiomfor Mat.Med.ofU.S.,V\a\3,^.ll9S.\\. 



(1833)169. ■^Pharm. Joum. v. (1864) 67. — Also 



^ Schopf, Materia Medica Americana, Bentley and Trimen, Med. Pla?i(% part 3 : 



Erlangaj 1787; 77.— Also Barton, Collec- (1878). 



