16 OUTLINE OF STRUCTURAL BOTANY 
pands. About the stem of the polygons the stipules take the form 
of tall collars while in the pea family the stipules in some species 
exceed the leaf in size and among the pondweeds it is often a long 
grass-like appendage. 
Referring to the diagrams on the succeeding page, we find a 
number of forms which, while each may not precisely represent 
all the leaves which are classed as belonging to that particular 
Fic. 19—Stipules Fic. 20—Stipules Fic. 21—Stipules 
of Rose leaf. of Clover. of Viola arenaria. 
form, are all sufficiently typical to indicate the class of the leaf- 
blade which might be under observation, provided the leaf under 
consideration is not compound. 
We may conveniently arrange them in the following table: 
TABLE OF SIMPLE FEATHER VEINED LEAF-FORMS 
I 
‘A single principal vein traverses the main axis of the leaf. 
The tissues intervening between the veinlets fully or mainly 
developed . . . . Feather Veined Forms. Pinnate-Veined 
The middle veinlet exceeds the others in length, the veinlets 
above and below becoming gradually shorter. 
The breadth of the widest part is: 
About equal to the length of the leaf (Fig. 1) . Orbicular 
About @ to £ the: length (Wig. 2))). 3°) 3) ae Oval 
About 4 the length (Mig. 8)... % 4... ) <a ee 
About + to 4 the length (Fig. 4) . 6 oy 6) a OER 
The veinlets of the lower third exceed the other side veinlets, 
which become gradually shorter above and below. 
The breadth of the widest part is: 
Nearly or quite equal to the length (Fig. 6) . . Deltoid 
About % the length, egg-shaped (Fig. 7) . . « . Ovate 
About 4 the length or less, lance-shaped (Fig. 8) Lanceolate 
