182 



POPULAR SCIENCE MONTHLY. 



wild peas ; matrimony vine is left to grow awhile among plants of bitter- 

 sweet, ground cherry, horse-nettle and buffalo bur; the Oswego tea 



Fig. 5. Twining Plant, Wild Morning-glory. (Reduced.) 



shies its rootstocks all about and many appear and remain for a time 

 with peppermint, spearmint, sage, origanum and motherwort; worm- 

 wood visits ox-eye daisy and the two agree well together; Canadian 

 golden-rod creeps into plats of low-land grasses, sedges, wild asters and 



artichokes; the enterprising dandelion is found 

 in plats of hawkweed, chicory, wild lettuce sow- 

 thistle, and is often overlooked; and squaw- weed 

 finds a welcome with sweet-colt's-foot. 



An Iris that imitates a Rattlesnake. — In por- 

 tions of Washington rattlesnakes are very abun- 

 dant, and are much dreaded by cattle and horses 

 which graze large portions of the state. 



In this region grow large quantites of Iris 

 fig. e. a cross section Missouriensis and when ripe the rattle of the 

 muchenlargedofablad- see( j m t j ie poc ] s c i 0S ely resembles the rattle of 



DER-LIKE Trap which « . • i -11 



catches worms. (After the snake. Grazing animals invariably step 

 Darwiu -> back after hitting these pods, and thus the 



green leaves of the plants are spared to work for future crops of 

 seeds. 



For this observation I am indebted to Matt Crosby, of the U. S. 

 Bureau of Forestry. 



