EPIGYNOUS MONOCOTYLEDONS 203 



water pimpernel, it is said to be sympetalous, meaning " of 

 united petals." Monopetalous and gamopetalous are other 

 words used to denote the same thing, and the kindred 

 terms, synsepalous, gamosepalous, etc., are applied to the 

 calyx. 



293. Dissection of the Iris. Sketch the outside of the 

 specimen, labeling the oblong, three-lobed enlargement at 

 the base, ovary, the prolongation of the flower above it, 

 tube of the perianth, the three outer lobes with the broad 

 sessile bases, sepals, the others, with their bases narrowed 

 and bent inward, petals. Now turn the flower over and 

 sketch the inside, labeling the three large, petal-like ex- 

 pansions in the center, stigmas. Do you see any stamens ? 

 Remove one of the sepals and look under the stigma; 

 what do you find there ? Notice the little honey pockets 

 at the foot of the stamen. Run the head of your pencil 

 into them and see what would happen to the head of an 

 insect probing for honey. 



Remove all the petals and sepals 

 and sketch the remaining organs in 

 profile, showing the position of the 

 stamens. Are the anthers extrorse 

 or introrse ? What is their mode 

 of dehiscence? Remove a stamen 

 and sketch it. What is the shape 

 of the anther? 



_. i r i 39- Vertical section of 



Remove as much of the upper iri f fl ower ; with perianth 



part of the perianth tube as yOU Can removed, showing a stamen 

 ... . . .. , ., and three stigmas: su, stig- 



without injuring the pistil, and with matic sur f ace . 

 a sharp knife, slice away a section 



down through the ovary so as to show the long style and 

 its connection with the placenta. Make a sketch of this 

 longitudinal section (see Fig. 389), labeling the long, club- 

 shaped stalk running from the ovary to the stigmas, 

 style ; the white column in the center of the ovary to which 

 the undeveloped seed are attached, placenta, and the unripe 

 seeds, ovules. Notice whether the placenta is central or 



