20 PELL.EA ORNITHOPUS. BIRD ROCK-BRAKE. 



It varies very much in size : sometimes plants fruiting perfectly 

 are but a few inches high. We have some fronds before us, sent 

 by Dr. L. D. Morse from San Mateo, which are nearly a foot 

 in length. This specimen has very few ternate pinnules. Our 

 illustration is a good average size, and was taken from a plant 

 o-rowine in the Arnold Arboretum, under Mr. Jackson Dawson's 

 care. 



It is now not uncommon under culture, and proves itself well 

 adapted to window gardening, not being so particular about a 

 moist atmosphere as many cultivated ferns are. 



Explanation of the Plate. — i. An average-sized plant with pinnules nearly all entire, only 

 a few being ternate. 2. An enlarged pair of pinnules, showing the broad indusium ex- 

 tending all along the margin of the frond. 



