THE PLANT GROUPS 139 



ASEXUAL REPRODUCTION 



1. Ovulate strobili of the spruce. Study surface views of 



mature dry strobili of the spruce and median long 

 sections of preserved strobili. 

 a. Gross parts. 



(1) Are the parts of the spruce strobilus the same as 



those of strobili in lycopods and cycads ? Are 

 there sporophylls ? a central axis ? ovules or 

 megasporangia ? Is the strobilus cyclic or spiral 

 in plan ? Study both surface and sectional views 

 of the strobilus to determine the above points. 



(2) Seeds. Do you find seeds or ripened megasporangia 



in the mature strobili? How are they adapted 

 to dissemination? 



(3) Drawings. Draw surface and sectional views of 



portions of the strobilus about one inch in 

 length. Draw the median section very accu- 

 rately. Label the parts in terms of sporophylls 

 and sporangia. 



1. Megasporopliyll, sporangium, and bract. Piemove sporo- 

 phylls from strobili and determine the relations of 

 the above structures. Construct a vertical sectional 

 view of bract, megasporophyll, and megasporangium. 

 Consult the text concerning the morphology of the 

 spruce strobilus. Is it a simple strobilus like that of 

 the lycopod or is it a branch system with bracts 

 corresponding to regular leaves ? To what do the cone 

 scales correspond ? 



2. Staminate strobili. 



a. Gross parts. Have the staminate strobili the same parts, 

 with a similar arrangement, as the ovuliferous strobili? 

 Have they both bracts and sporophylls ? 



