414 



PASTURAGE AND OVEKSTOCKING. 



Fig. 174. 



ASCLEPIAS TUBEHOSA. PLEURISY BOOT. 



Fig. 175. 

 ASCLEPIAS SYRIACA. 



plant), Veronicas, Yellow Jessamine of the South, 

 whose honey is poisonous.— (Dr. J. P. H. Beown".) 



Asclepiadaceae: — The common Milk- 

 weed (Fig. 175), or Silkweed, Aselepias 

 cornuti, is much frequented by bees, 

 but these visits are often fatal to them. 

 All the grains of pollen of the Silkweed, 

 in each anther, are collected in a com- 

 pact mass, inclosed in a. sack; these 

 sacks are united in pairs [a. Fig. 176) 

 by a kind of thread, terminated by a ^'ig. 176. 



small, viscous gland. These threads ''°^^"'' °^ milkweed. 



' ° a, sacs of pollen in 



stick to the feet. (6. Fig. 176) and often pa'rs; b, the same at- 

 to the labial palpi (46) of the bees, who (From "A b c of Bee- 

 cannot easily get rid of them, and perish. " "'^''' 



In some parts of Ohio and Western Illinois, a variety of the 

 common kind, the Aselepias Sullivantii, does not present to 

 bees these difficulties to the same degree. "We have seen bees 

 gathering honey freely on four or five different varieties 

 which grow in our neighborhood, and especially on the Tube- 



