88 



BOTANY. 



(a) Primary Meristem tissue may be readily obtained for study by 

 making thin longitudinal sections of the tips of growing shoots of 

 Equisetum, PTuxseolus, Hippuris, and the roots of Pteris, Zea, Impa- 

 tiens, etc., or by carefully dissecting out the youngest rudiments of the 

 leaves of many Monocotyledons. 



The value of the specimen will often be Increased by staining it 

 vrith carmine. 



(6) The apical cell, which may be seen in the best of the above-men- 



Fig 77.— The growing point of the stem of Equiietmn sdrpoides. A, seen from 

 without, showing the apical cell at the top ; the numerals 1, 3, 4, etc., indicate the 

 order of the I'ormation of the partitions of the apical cell; that marked 1 is the last 

 formed, 3 the third from the last, etc. ; between 4 and 7 on the right, and 6 and 9 on 

 the left, are the partitions which form after the primary ones; B, a VBrtical section of .4. 



tioned sections of Equisetum and Pteris, should also be studied by 

 making extremely thin cross-sections of the apical portion of the 

 Vegetative Cone ; the triangular shape of the apical cell can thus be 

 made out. 



The simple side view of the isolated Vegetative Cone is also instruc- 

 tive when so prepared that it can be rotated under the microscope. 



