1867.] Botany and Vegetable Physiology. 93 



Second covering of the fruit, ordinarily mesocarp; in conifers, 

 cellular substance between 3 and 5. 5. Third covering of fruit, 

 ordinarily endocarp ; in conifers, the testa. The remaining envelopes 

 of the nucleus of the ovuli in the conifers (primine, secundine, &c.) 

 in no respect differ in appearance or function from those of other 

 seeds, and therefore need not be specially noted. 



Lichenology . — The Eeverend W. A. Leighton continues his 

 series of papers on this subject in the ' Annals.' He has lately given 

 a notice of the Abbe Coeman's essay on the Gladonise, of the 

 Herbarium of the great lichenologist, Acharius, and the results of 

 the application to his own herbarium of a chemical test as a means 

 of deciphering species of Lichens. The reaction which is found so 

 useful, is that of hydrate of potash, which in certain cases produces 

 a yellow colour, whilst in others there is no reaction, or only a 

 slight fuscescence. In no case, says Mr. Leighton, is the reaction 

 of greater utility than in the difficult tribe of Cladonise, that crux 

 of lichenologists, where its application enables us with admirable 

 precision and exactness to determine the various species, to re- 

 distribute the confounded species, and to refer to their proper 

 systematic places the innumerable varieties and forms which may- 

 resemble each other in external character. 



Climbing Plants. — Herr Fritz Muller, who is so well known 

 among zoologists by his many valuable contributions to their 

 science, and more especially by his essay, entitled * Fur Darwin/ 

 writes from Desterro, in South Brazil, to Mr. Darwin, on 

 the subject of his paper on the movements and habits of climbing 

 plants. Mr. Darwin, in that paper, says that he has seen no 

 tendrils formed by the modification of branches, and even seems to 

 entertain some doubt whether such tendrils exist. Herr Muller 

 gives an account of various plants which are known to him 

 exhibiting this structural phenomenon, and traces the following 

 stages in the development of branch-climbers : — 1. Plants supporting 

 themselves only by their branches stretched out at right angles, 

 for example, Gliiococea. 2. Plants clasping a support with their 

 branches unmodified, Securidaca (Hippoeratia). 3. Plants 

 climbing with the tendril-like ends of their branches. According 

 to Endhcher, this is the case with Helinus (ramulorum apicis 

 cirrhosis scandens" ). 4. Plants with highly modified tendrils, 

 which may, however, be transformed again into branches, for 

 example, Hecastaphyllum, a Papillionaceous plant. 5. Plants with 

 tendrils used exclusively for climbing, Strychnos, Caulotretus. The 

 letter contains many other interesting observations, which may 

 be read in full in the Linnsean Society's ' Journal ' of November 

 29th. With respect to the thickness of the support which can be 

 ascended by spirally twining plants, Herr Muller states that he has 



