PTERIDOPHYTA— EOUISETACEAE 325 



case, though all were fed good, clean timothy hay, they seemed to prefer the horsetail 

 bedding, and even left their grain to eat it. 



Condition of the plant. — WIe have no evidence that horses grazing upon the green 

 plant are poisoned thereby. It may be that the plant is less poisonous in the early stages 

 of its growth than when mature, or the laxative effect of the grass eaten with it may 

 prevent the cumulative action of the poison. Moveover the plant rarely occurs in as large 

 quantities in pastures as in meadows and apparently rarely need cause apprehension. If, 

 however, it is abundant, close watch should be kept upon horses pasturing where it 

 occurs that the animals may be removed at the earliest symptoms of trouble. 



Treatment.— In the way of treatment, the first and most important thing is to stop 

 immediately the feeding of the Equisetum hay. Our practice further than this has been 

 to give a purgative pill consisting of one ounce of Barbadoes aloes, one or two drachms 

 of ginger, and sufficient English crown soap — soft soap — to make a ball or pill. This is 

 put down the horse's throat, at one dose, and following this we have usually given bran 

 mashes night and morning until the digestive tract is entirely cleared of the poisonous plant. 

 In case aloes cannot be easily obtained a quart of raw linseed oil will be very well. After 

 the physic has operated, a teaspoonful of powdered nux vomica is added to each grain 

 feed, three times a day. This tends to relieve the muscular incoordination. When poison 

 symptoms are severe and especially when staggering is very profound, slings should be 

 used to support the animal for when once down it is very difficult to make it stand 

 again even with the aid of slings. If, however, the above treatment is begun before the 

 horse loses the power to stand and it can be kept on its feet, its life can be saved in 

 practically all cases. 



Stebler & Schroter in their work on the weeds of meadows mention this 

 same plant and several other species as being injurious to stock, not only to 

 horses, about which there is a difference of opinions, but to cattle. In the latter 

 it produces diarrhoea. Cows become poor and the milk flow ceases or is checked. 



That this disease is similar to one produced by mouldy corn is shown by 

 the following quotation from Dr. Peters : 



It is also known that certain weeds commonly called horsetail have a faculty of pro- 

 ducing a disease almost identical with this one. The experiments conducted by Dr. Rich 

 of the Vermont Station show that that weed is capable of producing similar symptoms. 



EMBRYOPHYTA, ( SIPHONOG AMA, OR 

 SPERMATOPHYTA) 



Plants producing seeds which contain an embryo with 1 or more cotyledons, 

 a stem caulicle, a radicle, and a plumule, these parts, occasionally not dif- 

 ferentiated before germination ; microspores, equivalent to pollen grains borne 

 in microsporangia ; ovules (macrosporangia) borne on a modified leaf called 

 the carpel, containing 1 macrospore, equivalent to the embryo sac which de- 

 velops the minute female prothalhum, an archegonium ; the egg cell in the em- 

 bryo sac is fertilized by means of a sperm cell in the pollen tube; the male 

 prothallium generally but slightly developed. The Spermatophyta contain 

 two main divisions based upon the character of the ovules. 



GYMNOSPERMAE 



Ovules naked, not enclosed in an ovary, attached to scales or wanting; 

 pollen grains develop into the pollen tube; the male prothallium contains the 

 sperm cell and fertilizes the egg cell in the ovule. The Gymnosperms are di- 

 vided into six classes. 



1. Cycadales. These include the Cycas circinnalis well known in cultiva- 

 tion, an important plant of the tropics. The C. media of Australia produces 

 rickets, a Macrozainia causes the same disease. Dr. Stafford states that C. 



