The Nature and Origin of Stipules. 13 



Where a larger number of leaves occurs, an additional prominence 

 for each arises between the original stipular prominences.* 



Cauvet, D. — Probability de la Presence des Stipules dansquelques Mono- 

 cotyedones. Bull. Soc. Bot. Fr. 12 : 241. 1865. 



A number of cases are considered and the conclusion drawn that 

 very probably some Monocotyledones are provided with stipules, 

 bat the difference in their form and position has caused them to 

 be considered as another kind of organ. 



Median, Thomas. — On the Stipules of Magnolia and Liriodendron. 

 Proc. Acad. Nat. Sci. Phila. 114-116. 1870. 



Mr. Meehan argues for the origin of the stipules of Magnolia 

 as lobes of the lamina similar to the auricles which occur in M. 

 Fraseri Walt, by a union of the auricles with the upper surface 

 of the petiole, and a subsequent adnation of their margins and 

 separation from the lamina. He says, " It is scarcely possible to 

 avoid the suspicion that the stipules of Magnolia are not formed 

 like the stipules of most plants which are perhaps leaf portions 

 which have never been well developed, but rather are the tolera- 

 bly well developed side pinnules of a trifoliate or deeply auricled 

 leaf." 



Speaking of observations upon the flowers of M. fuscata Andr., 

 of East India, the following interesting statement is made : " This 

 observation confirms the views of some botanists as I have learned 

 from Professor Asa Gray, that it is by metamorphosis of the 

 petiolar and stipular parts, rather than by modifications of the 

 leaf-blade, that petals are formed." 



Duval-Jouve, J. — Sur quelques tissues de Joneses, etc. Bull. Soc. 

 Bot. Fr. 18 : 231-239. 1871. 



The presence of the ligule in the Juncacese is treated of. To quote 

 the author, " If in certain species the ligule is so reduced that it 

 appears to be lacking between the separated auricles at the apex 

 of the sheath, in most others these auricles are united by a true 

 ligule, as pronounced as that of grasses, either entire or cleft at 

 the middle." 



Dutaily, Gr. — Sur les variations de structure de la ligule des Graminees. 

 Bull, de la Soc. Linneene, 170. 1878. 



*F. Pax (Allgemeine Morph. der Pflanzen, 100. 1890) says, when there 

 are more than six parts to the whorl, the additional parts must have their 

 origin in a division of the blades of the stipules. 



