Dec. 19, 1884.] 



• KNOWLEDGE 



605 



Night Sign of the Month. 



and hard as that of a pin. Almost hiding this tip, and 

 extending upward to nearly half the length of the sted, is 

 a soft, silky, hair-like giowtb. The remainder of the seed, 

 which has a total length of about three quarters cf an 

 inch, is bare, smooth, and tlinty. A minute depression, 

 made by the unfolding of the edges of the case, runs the 

 entire length of the seed. 



From the upper end of the seed runs a long awn or beard, 

 varying in length from four to seven inches. This awn is 

 a simple but beautiful piece of mechanism, designed appa- 

 rently for the sole purpose of enabling the seed to sow 

 itself. It is tightly twis-ted, screw-like for two-thirds of 

 its length, and then turns abruptly into a light angle, the 

 remaining one-third beiug untwisted. They who are 

 acquainted with the so-called animated oats or the wild 

 oats will be familiar with the action of the twisted awn 

 under the iifluence of wet or dry weather. The awn 

 unloosens or tightens its twist according as it comes uiider 

 the iLfluence of wet or dry conditions, and the untwiited, 

 right-angled er.d remaining quiescent enables the seed to 

 writhe and turn and burrow deeper and deeper into the 

 earth. 



This application of its mechanical powers to the proper 

 end of saving its life is both beautiful and pleasing ; but, 

 unfortunately, those power's, being mechanical, act with 

 equal vigour to an improper end. Caught in the seemingly 

 impenetrable wool of the sheep, and there subjected to the 

 influence of alternate moisture and dryness, the awns do 

 their work, and, incredible as it may seem, propel the seed 



so far as to cause the needle to penetrate the hide of the 

 animal. The awns break ofi", and the needles penetrate the 

 vital parts of the sheep, causing painful death. The harn> 

 less-locking silky growth en the needle, tending backward 

 from the point as it does, acts as a barb to prevent any 

 retrograde movement of the intruding needle. 



The points, too, not only enter the body of the sheep ia 

 this way, but also stick in the nostrils, nose, and lips. 

 where, however, they do less harm than when eaten and 

 swallowed into the itomacb, in which event death must 

 follow. 



The tendency to underrate the work of weak agents may 

 lead to the thought that no material damage can be done 

 by means of the iSf-ipa spartea to sheep. How eironeous- 

 such a conclusion would le will be seen frcm a statement 

 of Mr. Henry Stewart, who, in his work, " The Shepherd's 

 Manual," says, refeiring to sheep in the Noith-Western 

 district, that "the most frequent losses are caused by a 

 native grass, which bears exceedingly sharp awn cr beards, 

 and called popularly 'needle grass.'" 



Sheepmen guard against loss from this cause by frequeni 

 examination of the sheep during the period when Stipyt 

 sparfea is ripe, and by buming the pasture in Jute, ai 

 which time the deadly grass has just commenced its 

 growth. Prevention in this instance, as in others, ia 

 better than cure, for it is no easy matter to examine 

 every sheep of a large herd so carefully that all the- 

 needles can be detected and withdrawn. — Scierdijh- 

 American. 



