150 



once to twice pinnate; (2) dwarfing; (3) increase in ruffling; and 

 (4) cresting. 



The second and third leaves and corresponding pinnae repre- 

 sent increased leaf division. The third leaf is from the "Anna 

 Foster" variety, the earliest of all the Boston fern sports, but it 

 was soon supplanted in the esteem of the florists by the "Pier- 

 son" fern, shown in the second leaf and pinnae, due to the more 

 desirable horticultural characteristics of the latter. From this 

 form alone, scores of secondary tertiary, and higher degree 

 sports have developed, resulting in various degrees of leaf divi- 

 sion, — as much as five pinnate,^ — and other modifications. 



Figure 3. Pinnae of the Boston fern and of the seven primary mutations, 

 arranged as in Figure 2. It is a simple laboratory exercise to have pupils make 

 outline drawings of a Boston fern pinna with one or more of the other types for 

 comparison. 



The fourth and fifth leaves and pinnae represent dwarf 

 types, respectively "Scott's" fern, of Brooklyn origin, and the 

 "Giatras" fern, Hoboken Greek. In addition to their smaller 

 size, each offers other differences in outline, marginal characters, 

 and configuration of the pinnae, as well as in habit of growth. 



The sixth and seventh leaves and pinnae present intensifica- 

 tion of the ruffling or waviness of the pinnae, horticulturally 

 known as crisping. The larger leaf (6) is called the "Harris" 

 fern, after its introducer, a Philadelphia grower. The other, the 

 "Roosevelt" fern, was introduced by an Ohio florist. 



Lastly, there is a crested or "fishtail" type of variation, which 

 occurs not infrequently in wild native species. In the Boston 



