Some Notes Regarding South African Pharmacology. 129 



noticeable, due to increase of the systolic contraction and lessening 

 of the diastolic expansion. Apparently the cessation of respiration 

 takes place after arrest of the heart. 



In each case all organs except the heart appeared normal. The 

 latter organ was removed and embedded in paraffin blocks, sections 

 of which have been made for examination under a low power of the 

 microscope. 



It may here be noted that the wood of Acocanthera venenata 

 contains about -33 per cent, of the active principle. We have 

 as yet no data upon which to calculate the minimum fatal dose of 

 this plant, although Smith * records that 15 grains of the dried 

 leaves is the largest safe dose, but as regards Acocanthera Schimperi 

 Fraser and Tillief state that by sub-cutaneous injection the mini- 

 mum lethal dose of Acocantherin is --J^ to i ^ u of a grain per lb. 

 weight of a rabbit, from which it may be assumed that, for an 

 average man, J to -J- of a grain of the purified Acocantherin may 

 be fatal. 



The contraction of the heart that I have repeatedly alluded to is 

 very characteristic in Acocanthera poisoning, and as soon as I 

 became alive to this fact I suggested that the importance of record- 

 ing the condition of the heart at post-mortem examinations should 

 be impressed on District Surgeons in the part of the Colony where 

 Acocanthera flourishes. It had been of frequent occurrence that 

 where the heart was not organically diseased no remarks were 

 made about its condition ; an important link in the investigation 

 may thus be missed. This point, I am glad to say, is now being 

 attended to. 



In a case which appeared in 1903 at Butterworth, a native woman 

 died from the effects of administration of a root by a Kaffir medicine- 

 man : the post-mortem examination showed that paralysis of the 

 heart in systole had occurred, and the fine shreds of the root, 

 examined in the Grahamstown Laboratory, exhibited the character- 

 istic reaction for Acocanthera when treated, with sulphuric acid, light 

 pink, gradually becoming violet. A decoction was made from 15 

 grains of the powdered root, and half an ounce of this was 

 administered to a healthy dog, eight months old. Eepeated emesis 

 occurred within 20 minutes, accompanied by violent straining and ab- 

 normal increase of secretion of saliva, such as is always noticed when 

 this drug is administered to dogs. These symptoms were accom- 

 panied by great muscular weakness and tremors, apparent giddiness, 

 retarded pulse and respiration. The emetic effects ceased after two 



* " South African Materia Medica," 3rd eel., p. 38. 



f " Acokanthera Schimperi : Its Natural History, Chemistry, and Pharmacology." 



