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The venation is also a character which shows the transition 

 between the simply pinnate veining of Phellos and the more 

 complex branching of the broad, lobed forms. The acorns vary- 

 in shape from ovoid to almost globose, and, in size, from those of 

 Phellos to others almost an inch in length by ^ in. in diameter 

 at the largest part. The cups are invariably saucer shaped, with 

 closely appressed scales. 



I made a special journey late in the season, to ascertain, if 

 possible, whether anything could be learned from the autumnal 

 coloring of the leaves, but I found them to be a uniform light 

 yellow, turning brown. 



From these observed facts I have finally come to the con- 

 clusion that we must consider. Q. heterophylla to be a hybrid, and 

 further, that one of the parents is Q. Phellos. They are invariably 

 associated together, or at least the former has never been found 

 except in the immediate vicinity of the latter ; and, added to 

 this, we know that Q. Phellos does produce a hybrid with Q. 

 nigra and that this hybrid occurs associated with Q. heterophylla. 

 It would not, in fact, be a matter of surprise to me if we should 

 eventually find that other hybrid forms have resulted from the 

 influence of Q. Phellos over other species of the black oak 

 group. As to the other probable parent of Q. heterophylla 

 there is yet room for careful research, although I think that 

 the discovery of these trees on Staten Island has considerably 

 simplified the matter. The species mentioned by those who have 

 written upon the subject are aguatica, imbricaria, falcata, coccinea, 

 tinctoria and palustris. The first three may be thrown out of 

 the calculation at once on account of their geographical range — 

 not a single specimen of either having ever been found or reported 

 within miles of our station. Coccinea and tinctoria, while show- 

 ing a leaf form that is satisfactory, have acorns with deep 

 cups, entirely distinct from those of heterophylla. Palustris 

 has a cup of the required form, but the acorn is far too small, and 

 the lobes of the leaves have a distinctive divergent characteristic 

 which those of heterophylla have not. The only other probable 

 species, and it is the only one which does not seem to have been 

 considered by our botanists, is rubra. Why this species has not 

 received the attention it deserves in this connection I am at a loss 



