JUGLANDALES. 109 



Description'. — Leaves variable in size, i.i. cm. to 5 cm. in length 

 by 0.4 cm. to 2 cm. in breadth, ovate lanceolate in outline with an 

 obtusely pointed apex and a cuneate, slightly decurrent base. 

 Margin divided into from 2 tO' 4 slightly aquiline, rounded, 

 obtusely pointed lobes, the intervening rounded sinuses cut about 

 half way to the midrib. Secondaries craspedodrome, one to 

 each lobe. In the larger leaf there is a second secondary some 

 distance below the one which traverses one of the lobes, and, 

 while this is not visible throughout its length, it was probably 

 camptodrome as in the leaves of the modern Coniptonia. 



It is difficult to understand on what ground Prof. Heer 

 founded his two species parviila and parvifolia unless it Vv'as 

 because they were supposed tO' have come from different geo- 

 logical horizons. He compares both to the European Conip- 

 tonia ceningensis Al. Br., although their resemblance to that 

 species, as a matter of fact, is not very close. The two are ex- 

 actly similar, as is the Rhus included in the foregoing synonymy, 

 except as to size. The Raritan specimen which Newberry identi- 

 fied as parvula is closer to parvifolia, which fact is noted by the 

 latter author, who presumably hesitated to refer a Cretaceous 

 leaf to a species of the Miocene, as these Arctic deposits were 

 thought to be at that time. The writer has elsewhere (loc. cit.) 

 called attention to the probability of Heer's specimens having 

 come from practically the same horizons, so that there are no 

 valid reasons for maintaining their fancied distinctness. 



The earliest leaves of the modern Comptonia peregrina 

 (Linne) Coulter usually are very similar to this fossil species. 

 These latter might be considered as the abbreviated leaves, so 

 common in seedling plants and hence without phylogenetic mean- 

 ing, or they may be considered as representing the normal leaves 

 of these ancient Comptonia plants. The first assumption seems 

 doubtful, not only because of the perishable nature of seedling 

 leaves in general, but because it is unusual for them to become 

 detached and fossilized, and it would be a rather singular coin- 

 cidence for this to have occurred in New Jersey, Greenland, and 

 Europe only once and at the same geological horizon. Further- 

 more, no other species of Comptonia are known from either the 

 Raritan clays, or the Atane and Patoot schists, from which they 



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