Maryland Geological Survey: 387 



outline than in N. longifulia; broadest toward the rounded base, the 

 maximum width observed being 1,5 cm. although the average width 

 is much less and may be put at 1 cm. or slightly less ; very variable in 

 size, tip generally acute although an occasional specimen may be obtuse. 

 The greatest length observed is 8 cm. but the average length is much 

 less than this and may be placed at 3 to 4 cm. Occasional twigs like the 

 solitary specimen described as N. decrescens or the specimens referred 

 to N. microphylla may be much smaller thart, the above. The latter are 

 however of the same general shape while in the former case the fact 

 that the larger leaves at the base of the specimen are replaced by very 

 minute leaves indicates that the specimen is an abnormal twig. Veins 

 fine in calibre, somewhat remote, generally 6 to 9 in number, forking at 

 the base and diverging rapidly at first, then parallel until they alnit upon 

 the margin. 



While it might seem at first sight that too great a variety of leaf 

 foiTus had been lumped under this specific name the great variability 

 of the leaves on single tjwigs should be kept in mind. The leaves in the 

 type forms are commonly smallest toward the base of the twigs as they 

 are also in the N. ovata forms. In TV. decrescens the basal leaves are 

 100 per cent longer than are the succeeding leaves. In the forms 

 described by Fontaine as N. heteropliylla the leaves are especially varia- 

 ble, some being identical with those he called N. niicruphylla while others 

 are like those he calls N. decrescens, other still simulating his N. ovata 

 and N. zamioides with two or more of these types present on the same 

 twig. Others referred by him to N. zamioides show an equally wide 

 range of variation. Fig. 1 on pi. Ixiii shows a figure of a small specimen 

 labelled N. zamioides which has but five leaves and includes leaves easily 

 referable to Fontaine's species microphylla decrescens, ovata, lieterophylla 

 and zamioides leaving only his N. recurvata to be accounted for. Since 

 these latter are detached there is really no proof that they are correctly 

 identified. They are, however, exactly like certain somewhat falcate 

 leaves of N. zamioides found on twigs among normally straight leaves, 

 so that there is little doubt but that the Virginia specimens are refer- 

 able to this species. The form identified as N. recurvata from Vinegar 



