

1 '. t li PROCEEDINGS OF THE \ \ll<>\ \i. UUSEl I/, vol. 88. 



and diverging rapidly al first, then parallel until the} abul upon the 

 margin. 



While ii might seem al first sight thai too greal ;i variety of leaf 

 form had been lumped under this specific name, the greal variability 

 of the leave on single twi^s should be kepi in mind. The leaves in 



the type forms are c monly smallest toward the base of the twigs, 



as the} are also in the \. ovata forms. In N. decrescens the l>;is;il 

 leaves are one hundred percenl longer than are the succeeding leaves. 

 In the forms described by Fontaine as N. heterophylla the leaves are 

 especially variable, some being identical with those he called \. 

 microphylla, while others are like those he calls A. decrescens, others 

 till simulating his A', ovata and A', zamioides with two or more of 

 these types present on the same twins. Others referred l>\ him in 

 \ amioide8 show an equally wide range of variation. I have figured 

 (fig, 2) a specimen labeled A', zamioides which shows bul five leaves, 



ami includes leaves easily referable to his 

 species microphylla decrescens, ovata, heter- 

 ophylla, and zamioides, leaving only his A'. 

 recurvata to he accounted for. Since these 

 V latter are detached, there is reallj no proof 



I hat t hey are col reel ly idenl ilied. They are, 

 v however, exactly like certain somewhat fal- 

 cate leaves of A'. <iini<>hl<s found on twigs 

 a ng normally straight leaves, so that 



there is little doilhl hill that the Virginia 



specimens are referable to this species. The 



p W iooi iqeiop i zaw form identified as A', recurvata from Vinegar 



winq vabiatio i Hill, Maryland, is different from the others 



FORM ANI I VI . ' . , 



and IS a I <></<> ilinih s leallet. ( orrohorale 



evidence is furnished by the similarity in venation characters and in 



the fact thai all hill one of I he six so-called species, A'. i/< cr< set us, are 



from the single limited exposure at Fredericksburg, ami this was 

 described from a near hv ami probably synchronous outcrop ami is 

 ii'.illv presenl al Fredericksburg attached to a twig labeled N. hetero- 

 phylla. Four of i hem are again associate! I a i tic Dutch Gap locality. 

 Again ai Fredericksburg the typical amioides of Fontaine are very 



abundant, while the variants which he described as separate species 



are represented in some cases by a single specimen, in others hv but 

 two or three specimens. I think a glance at the various figures in 

 Fonti >'s monograph and a perusal of the accompanying descrip- 

 tion will be convincing, and this is onlv emphasized l>.\ a consulta- 

 tion of the speci men t hemselves. 



Compare, for example, fig. 5 of ovata with fig. 3 of amioides and it will 

 be seen thai thej might have \<rfw drawn from the same specimens. 

 This is likewise true when the single specimen of A', decrescens is 



