CERATOPTERIS THALICTROIDES. THE HORNED FERN. I 47 



natural system of Botany was made popular by the labors of A. 

 L. de Jussieu, and the more natural groups of species gathered 

 into distinct bodies, this great author enumerates only fourteen 

 genera in all the large family of ferns. The separation from 

 Acrostic/mm and formation into a separate genus as Ccratopteris 

 dates from 1821, by Brongniart, who described and named it in 

 a French work, the " Bulletin de la Societe Philomatique," but 

 some authors contend that Kaulfuss had named and described 

 it as Etiobocarpus, a little before this, and so the plant has to be 

 sought for in some European works under this name. However, 

 Sir W. J. Hooker insists on Ccratopteris as being the prior, and 

 hence the correct name. Ccratopteris is derived from two Greek 

 words meaning " horned " and " Fern," and this name was evi- 

 dently suggested by the reflexed margins of the frond meeting 

 at the back, as noted in the description, which give the sori the 

 appearance of being enclosed in a hollow horn. To some of 

 the older botanists it was known as Acrostichum siliqicostu??, the 

 specific name having been suggested by the same circumstance, 

 that is, the rolled pinnule appearing like a silique, as the hollow 

 seed-pods of cruciferous plants are termed. The specific name, 

 thalicti'oidcs, is, of course, from a supposed resemblance in the 

 fronds to some species of Thalictruin, or " Meadow-rue." 



The anatomical structure of this fern gives it a more than 

 usual interest to the botanist. The rings which surround the 

 sporangia in ferns are nearly obsolete in this, and Sir W. Hooker 

 was, therefore, at one time disposed not to regard it as a true 

 member of the fern family. Again, it is peculiar in being an 

 annual, while ferns in general are perennials, carrying over their 

 rhizome or root-stocks from year to year. Like annual plants 

 in other families, nature has made up for the shortness of its 

 individual life by giving to it the means of rapid propagation. 

 The spores are not as numerous as in most other ferns, but they 

 have powers of ready germination, and Mr. John Smith, in his 

 " Historia Filicum," observes that, in the plant-houses of Kew 

 Gardens, young plants appeared wherever there was a moist 



