?36 



CCXX. CEEATOPHYLLE^. 



Veratophyllum. 

 (J flower (mag.). 



Cej'atophi/Uum. 

 Young stamen (mag.). 



Ceratophyllum. 



Transverse section of 



anther (mag.). 



Ceratophyllum, 



Adult stamen with 



dehiscent anther (mag.). 



Ceratophyllum submersum. 



Cei-atophyllum. 



Vertical section of 



fruit (mag.)' 



Ceratophyllum. 



Vertical section of young 



ovary (mag.). 



Ceratophyllum. 

 Embryonic sac with 

 the first p,ppearance 



of the embryo 

 (mag.). 



Ceratophyllum, 

 Young pistil (mag.). 



Ceratophyllum. 

 Adult pistil (mag.). 



Ceratophyllum. 



Seed, showing the 



embryo through the te&ta ; 



chalaza at th^ top. 



Ceratophyllum, 

 Embryo laid open, 

 showing the 2 cotyle- 

 dons, and the plumule 

 in the centre (mag.). 



The affinities of Ceratophyllecs are not obvious; they have, like ChlorantliacecBj opposite leaves, 

 diclinous achlamydeous flovrers, a 1-celled 1-ovuled ovai'y, and a pendulous orthotropous ovule ; but they 

 are aquatic^ their leaves , are capillary, and their seed is exalbuminous.. They have the same analogies 

 with UrticecBj but in this family the flower has a perianth, and the ovule is basilar. They resemble 

 CallitrichinecB only in being aquatic and achlamydeous, and having involucrate flowers and a 1-celled and 

 1-ovuled ovary. Brongniart was the first to point out the similarity of structure between the seeds of 

 Ceratophyllum and of Kelumbium (page 210). 



This family is composed of a small nuniber of species inhabiting stagnant water in Europe, Asia, and 

 North America. They possess no known useful quality. 



