THE LEAF-TRACE IN SOME PINNATE LEAVES. 
29 
species with a basipetally-developed leaf (Eichler, ’61, p. 19), and in Sambucus nigra , 
Linn., the leaf of which is also developed basipetally (Massart, ’94, pi. iii, fig. 49). 
In Heracleum Sphondylium, Linn., and Daucus Carota, Linn., the leaves are 
developed in acropetal fashion (Eichler, ’61, p. 18) ; the leaf-trace has some nine 
separate strands forming a curve on the abaxial side and stretching towards the 
adaxial corners ; two strands are present in the pith, on the antero-posterior line 
across the petiole. The intramedullary strands link up with all but the median 
abaxial strand when the pinna-traces are to be given off and assist the strands of the 
adaxial margins of the leaf-trace in giving the supply to the pinnae. 
Examples have now been described from woody and herbaceous plants with acro- 
petally- and basipetally-developed leaves. In the woody plants with acropetally- 
developed leaves the leaf-trace is of the closed type ; the pinna-traces come from its 
corners nearest to the pinnae. In the woody plants with basipetally-developed leaves 
the leaf-trace is open on the adaxial side and the pinna-traces come from its adaxial 
margins. 
Both types of leaf-trace are found among woody plants ; the open type prevails 
among herbaceous plants. 
In herbaceous plants with basipetally-developed leaves the leaf-trace is of the 
type found in woody plants with basipetally-developed leaves, and the pinna-traces 
arise just as in these plants. But in the two examples of herbaceous plants with 
acropetally -developed leaves there appear between the adaxially-directed arms of 
the leaf-trace curve additional strands which assist in the formation of the pinna- 
traces. We have thus : 
Woody plants. 
Herbaceous plants. 
Rosa arvensis , Huds. 
,, canina, Linn. 
„ tomentosa, Sm. 
Sambucus nigra , Linn. 
Spirxa Aruncus, Linn. 
„ Lindleyana, Wall. 
„ sorbifolia, Linn. 
Staphylea pinnata, Linn. 
Daucus Carota, Linn. 
Heracleum Sphondylium, Linn. 
Potentilla Anserine, Linn. 
Spirxa lobata, Murr. 
Leaves acropetally-developed. 
Leaves basipetally-developed. 
Daucus Carota, Linn. 
Heracleum Sphondylium, Linn. 
Spirxa Aruncus , Linn. 
„ Lindleyana, Wall. 
„ sorbifolia, Linn. 
Staphylea pinnata, Linn. 
Potentilla Anserina, Linn. 
Rosa arvensis, Huds. 
,, canina, Linn. 
,, tomentosa, Sm. 
Sambucus nigra, Linn. 
Spirxa lobata, Murr. 
