I 8 PELL.EA ORNITHOPUS. BIRD ROCK-BRAKE. 



rio-idus, badius," " from whence I have given it the name of Pcllcea 

 — baditis being the Latin adjective denoting a chestnut-bay or 

 sorrel color;" and, as we see, from the stipes or stalks, and not 

 " from the fronds." The color of the stalks of a fern would not, 

 of course, do to build a genus on, but the polished brown stipes, 

 as we see in our plate oi Pel I a: a oniithopus, is so common to 

 many of the genus that it was a good thought to take this char- 

 acter for the litde important meaning of a family name. Previous 

 to Link's time the species of this genus were classed with Pieris, 

 a well-known family of Ferns, and from which, indeed, they 

 differ so litde in the characters usually adopted for genera, that 

 Professor Wood, in one of the edidons of his " Class-Book of 

 Botany," might seem jusdfied in remarking that "their separation 

 to a new genus is an over-refinement." It is, however, a case 

 where the general appearance suggests a difference which science 

 has not been able clearly to define. For instance. Chapman, in 

 the " Flora of the Southern United States," describes Pte7as as a 

 genus having " sporangia borne on a transverse marginal recep- 

 tacle connecting the ends of the veins," while Pellcsa is described 

 as having " fruit dots oblong or linear at the ends of the veins, 

 confluent in a broad marginal line of frucdfication ; " but the 

 student will understand that he has a Pcllcea much more readily 

 from the general appearance of the plant than by the nice dis- 

 tincdons this nearly synonymous language conveys. Mr. John 

 Smith well remarks that the " normal puncdform sori (that is, the 

 fruit dots) of some species of Pellcea are so united as scarcely to 

 differ in technical character from Pterisr Then there are other 

 genera, such as Allosorus and Chcilanthes, from which it is often 

 difficult to distinguish some species of Pellcea. 



Plants of the genus Pteris are known as " Brake " or " Brac- 

 ken," and under this name especially the Pteris aquiliiia is known 

 in English poetry, as well as in popular English literature gener- 

 ally. The use of this word in connection with this class of ferns 

 comes from very ancient times, and is believed to be derived from 

 an ancient Saxon word similar to it, and having the same mean- 



