viii] Plants which cause Mechanical Injury 101 



Anthemis arvensis L. (Corn Chamomile). 



Anthemis Cotula L. (Stinking Mayweed). 



Artemisia Absinthium L. (Wormwood). 



Conium tnaculatum L. (Hemlock). 



Hyoscyamus niger L. (Henbane). 



Matricaria Chamomilla L. (Wild Chamomile). 



Pinguicula vulgaris L. (Butterwort). 



Senebiera didyma Pers. (Lesser Wartcress). 



Sium angustifolium L. (Lesser Sium). 



Sium latifolium L. (Water Parsnip). 



Tanacetum vulgare L. (Tansy). 



Thlaspi arvense L. (Penny Cress). 

 (See also Index " Milk, plants afiecting," p. 117.) 



PLANTS WHICH CAUSE MECHANICAL INJURY. 



There are a number of plants which, while not necessarily physio- 

 logical poisons, may induce injuries of a severe character when taken 

 by animals, and by causing festering may bring about septic poisoning. 

 For example the sharp pointed fruits of Stipa pinnata and Nardus stricta 

 may cause injury to the skin and mouth, piercing the palate and causing 

 inflammation, and when eaten may even perforate the wall of the 

 intestine and cause death ; and the awned glumes of species of Bromus 

 or the spikelets of Hordeum may injure the gums, causing inflammation, 

 ulceration, sores, the formation of pus, and loss of teeth. The Bromus 

 and Hordeum, also, together with over-matured "heads" of Trifolium 

 incarnatum, may give rise to phytobezoars or balls in the stomach of 

 horses and cattle (60, 119). The sharp pointed fruits of Erodium 

 cicutarium may cause local irritation by working into the wool of sheep. 

 Aira caespitosa may also cause injury to the mouth of stock. 



A case is recorded in New South Wales in which cattle and horses 

 ate Shepherd's Purse {Capsella Bursa-pastoris). The cattle were 

 unaffected, but the horses scoured, though most of them soon recovered 

 when removed from the cultivated paddock containing the weed. Two 

 young horses, however, showed signs of colic, became bloated, and 

 died. It was then found that they contained balls of fibrous material 

 (one weighed 1 lb. 9^ oz.) which consisted to the extent of nearly 50 per 

 cent, of fibres from Shepherd's Purse, and death was due to simple 

 mechanical obstruction of the bowel (155). 



Chickweed {Stellaria media) has been found to cause digestive disorder 



