192 



Aquifoliaceae. 



looked for, they are of diagnostic value as between Ilex and 

 Nemopanthus. 



On the large-leaved evergreen 

 hollies some leaves are entire and 

 others pungently toothed in the 

 same species sometimes even on 

 the same plant, and correspond- 

 ents of the Gardeners' Chronicle 

 (1853, pp. 630, 646; 1864, p. 25) 

 have discussed this. Assumption 

 that the toothing of leaves within 

 reach of grazing animals is a pro- 

 tective adaptation which is lost 

 when it becomes unnecessary is 

 typical of many teleological as- 

 sumptions that have brought the 

 entire category of so-called adap- 

 tations into more or less unde- 

 served disrepute. The idea of 

 aging or maturity, paralleled in 

 the ivy, as causative is embodied 

 in Gaudin's name, Ilex Aquifo- 

 lium senescens, for the entire- 

 leaved holly of Europe. 



1. Deciduous. 2. 

 Evergreen. 10. 



2. Twigs dingy-tomentulose. 

 Twigs at most sparingly puberulent. 3. 



3. Often very divaricately twiggy. 

 Not stiffly twiggy. 4. 



4. Buds appressed, pointed. 5. 

 Buds spreading, blunt. 6. 



5. Buds 2 mm. long: pedicels short. 

 Buds smaller: pedicels very long (15 mm.) 



6. Bud-scales obtuse: sepals ciliate. 7. 

 Bud-scales acute: sepals glabrous. 9. 



(1). I. serrata. 

 (2). I. decidua. 



(3). I. monticola. 

 (4). I. geniculata. 



