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Transactions. 



palisade layer, except near the lower epidermis. Rounded masses of crystals 

 of calcium oxalate occur fairly abundantly in the spongy parenchyma. 



The midrib is surrounded by round -celled parenchyma, amongst which, 

 directly above and below the xylem-strands, and close to the latter gene- 

 rally., occur little groups of small cells. These may be part or all of the 

 phloem, which Solereder* says occur in the stem on the inside of the xylem. 

 and in groups in the pith, as well as outside the xylem. Staining with 



Fig. 3. — T.S. of adult leaf of Parsonsia heterophylla, passing through 

 part of the midrib. The groups of small cells in the 

 midrib are probably phloem. X 167. 



eosin failed to prove the presence of sieve -tubes. In the mesophyll the 

 vascular bundles are surrounded by large parenchyma cells, which contain 

 chlorophyll. 



Leaves of the young stage of this species often contain a red colouring- 

 matter, besides the chlorophyll, in the upper row of the palisade cells and 

 in the lowest of the spongy parenchyma cells. This colouring-matter is 

 soluble in alcohol, dissolving out and leaving the green chloroplasts. It 

 answered tests for anthocyanin, being changed to a blue by a strong base. 



There is no other difference in the anatomy of the adult and juvenile 

 leaf-form. 



The anatomical characters of the leaf of Parsonsia heterophylla seem to 

 be altogether mesophytic, and there seems to be little device to protect 

 against or to increase the effect of radiation, except the fairly thick 



♦Solereder. H. : "Systematic Anatomy of the Dicotyledons." Translated by 

 L. A. Boodle and F. E. Fritsch. vol. 1, p. 531.' 



