SINUSES OF LEAVES. 



425 



6. Quadrangular, quinquangidar, &c. four-cornered, five* 

 cornered, &c. when four or five prominent angles lie round the 

 disk. 



7. Deltoid, shaped like a delta* ; when the figure is a rhom^ 

 bus ; that is, having four angles, of which the two lateral ones 

 are less distant from the centre than those at the extremities. 



8. Rotund, round ; when it has no angles. 



Ill, Sinus, a hollow, is a term used to express those openings 

 or cavities in leaves, which distinguish them into parts : in re- 

 spect to these, leaves are said to be, 



1. Reniform, kidney-shaped; when they are roundish, and 

 hollowed at the base, without any angles. 



2. Cordiform, heart-shaped ; when they are ovate, and hol- 

 lowed at the base, and the hinder or lower part has no angles. 



3. Lunulate, moon- shape d ; when they are round, and hol- 

 lowed at the base, and the lower part has no angles. 



4. Sagittate, arroiv -shaped ; when they are triangular, hol- 

 lowed at the base, and are furnished with angles at the lower 

 part. 



5. Hastate, javelin- shaped ; when they are triangular, the 

 base and sides hollowed, and the angles spreading. 



6. Pandur2Eform, pandure-shapedf ; when they are oblong 

 broader above than below, and contracted in the sides. 



7. Fissa, cloven; when they are divided by linear sinusses, 



* A Greek letter so called. The figure of the delta is a-triangle, which does not 

 exactly answer to the character here given of a deltoid leaf. 



f A musical instrument of the lute kind, but now disused: the shape of it, as 

 given by Marsenas, Harm. Instr. 1. 1. does not answer to that of the leaves here 

 explained; the figure of which comes nearer to that of the body of a violoncello or 

 violin. Author. 



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