THE AMERICAN BOTANIST. 47 



pies and the like. Juice, which when first issuing from a 

 plant is liquid, very quickly hardens. Such is the case 

 with many milky secretions. An ant climbing a stem, 

 punctures the epidermis with his sharp claws, when at 

 once the milk exudes, quickly sets, and holds the intruder 

 an unwilling victim. He will try to cleanse one foot and 

 thus mire others, and often perish miserably where he is 

 first caught. The use of acrid secretions is well seen in our 

 common tall buttercup, which, until cut and dried, is well 

 avoided by our grazing cattle. Often herds will shun 

 some plant which to us exhibit no obvious cause of avoid- 

 ance; they simply don't hke it. Bad or pungent odors, 

 like that of chamomile, are powerful preventives of ag- 

 gression. 



In Bell's "Nicaragua," one of the most charming 

 books of natural history travels ever written, we are told 

 of a species of acacia which is singularly protected by ants. 

 These liv€ in the hollow stems or thorns, and when the 

 plant is touched or roughh^ shaken, emerge in swarms for 

 its defence. No doubt their primary object is self-protec- 

 tion ; but in repelling their o\vn enemies thej^ guard as 

 well the shielding tree. Indeed, in some species of Myrme- 

 codia from the East, it would seem that the life of plant 

 and ant was so inter-woven that neither could exist with- 

 out the other. 



Brown University, Providence, R. L 



COLLECTING SLEDS. 



BY AI. F. BRADSHAW. 

 T^OTANY, always interesting, becomes absorbing when 

 '^ one has to search for a new plant. Having become 

 acquainted with the plants of my locality so well that 

 finding a new one marks a red letter daj^ I was wonder- 

 ing last spring where I would find material for study. 



One da3r it occurred to me to collect and stud3^ seeds 

 for a special work this summer. While I was considering 

 whether it would not be a lot of drudgery for a very little 

 gain and whether it might not be rather ridiculous to add 



