EOCKWEED 293 



elevation noticed on the surface of the thallus ? 

 Examine under the high power. From what 

 part of the conceptacle do the hairs grow ? 

 What is their structure ? Are they simple or 

 branched ? What tissue forms the wall of the 

 conceptacle ? Do you find anything but hairs 

 in these conceptacles '( Examine both transverse 

 and longitudinal sections to get views of con- 

 ceptacles from different directions. Look over 

 your sections for conceptacles in various stages 

 of formation. Are they formed in the same 

 manner as vesicles ? Draw. 

 The male conceptacles. — With a razor cut 

 transverse sections through the end of an alco- 

 holic branch bearing male conceptacles, and ex- 

 amine under a low power. What is the shape 

 of the section ? What sort of tissue occupies 

 the centre? The edge? In what part of the 

 section do you find the conceptacles? Does 

 their position correspond with that of the ster- 

 ile conceptacles ? Do you find the same parts, 

 ostiole, hairs, etc., as in the sterile conceptacles ? 

 How do the male compare with the sterile con- 

 ceptacles in size ? Draw. 



Study the sections under the high power. Ex- 

 amine again the tissue composing the centre of 

 the section. Of what kind of cells is it formed ? 

 How are they joined together ? What do they 

 contain ? Do these cells entirely fill the centre 

 of the section ? Can you now account for the 

 feel of the end of the branch when passed be- 

 tween the fingers? Examine the hairs. Are 

 those which fill the cavity of the conceptacle 

 at all different from those which project through 



