CHAPTER 4 

 GYMNOSPERMOUS POISONOUS PLANTS 



The plants treated of in this chapter are members of the division of 

 seed plants, Spermaphyta, but their seeds are naked at maturity not 

 inclosed in some seed vessel, or fruit. They are mostly resinous shrubs 

 and trees with evergreen leaves (the deciduous cypress and larch being 

 exceptions). They are included with Class GYMNOSPERM.E, which com- 

 prises the sago palm (Cycas), ginkgo, yews, pines, junipers, etc. within its 

 confines. 



Yew (Taxus canadensis). This low spreading shrub is found in woods 

 from Newfoundland to New Jersey, southeastern Pennsylvania on north- 

 facing slopes and Virginia west to Wisconsin, Iowa and Minnesota. It 

 contains the bitter-tasting alkaloid, taxin (CavH^NOio) which acts as a 

 heart depressant. The plant on account of its reputed poisonous character 

 is called poison hemlock in some places. The bark leaves and seeds are all 

 poisonous. The reddish, sweetish aril surrounding the seeds, is not poi- 

 sonous and is eaten freely by fruit-loving birds. 



Cases and Symptoms. Many cases of poisoning and of death of ani- 

 mals from eating the fresh foliage have been recorded in the veterinary 

 journals, and yet there are contradictory statements as to the results of 

 eating the foliage of this spreading bush. The symptoms of poisoning are : 

 Death may be sudden, resembling apoplexy. It may be preceded by stag- 

 gering and convulsions and in cases of long standing there is gastro-enteri- 

 tis. "There is a pronounced slackening of respiration and circulation, the 

 pulse being small, slow. Sensibility is diminished. There is a fall of 

 temperature, the skin and extremities being cold. The head is lowered, 

 the eyes are closed and there is decubitus. In some cases pregnant ani- 

 mals have aborted. In the horse, there are muscular tremors and fre- 

 quent urination. In cattle and sheep rumination is suspended and there 

 is more or less pronounced tympanites, with eructation, nausea and some- 

 times vomiting. Pigs bury the head in the litter and sleep, their sleep 

 being interrupted frorn time to time by nausea and groaning; or the ani- 

 mals rise, stagger about, and lie down again. With fatal quantities the 



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