ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 535 



to this contact and to gravitation, the absence of light is also a factor 

 in determining on which side of the thallus the root-hairs shall be 

 produced. Precisely the same results were obtained with gemmaa of 

 Lunularia. The author confirms, on the other hand, the assertion of 

 Pfeffer that the organic upper side of the thallus of Marchantia is 

 always the side which faces the light. This was determined by culti- 

 vating the thallus both of Marchantia and Lunularia on the surface of 

 water. He considers these observations to have an important bearing 

 on those of Leitgeb and Prantl * on the bilateralness of the prothal- 

 lium of ferns. 



Goebel's Muscineee.'j' — In his most recent account of the Musci- 

 neae, Dr. K. Goebel introduces no fresh element into the main 

 principle of their classification. The Hepaticae are divided into two 

 main groups, the Marchantiaceae (subdivided into the Riccieae, Cor- 

 sinieae, and Marchantieae) and the Jungermanniaceaa (Jungermannieaa 

 and Anthoceroteae). In the Musci he groups the Sphagnaceaa and 

 Andreaceae together as one type, the Phascaceae and BryineaB together 

 as a second type. In each group the various organs are treated in 

 succession : — Firstly, the vegetative organs and the non-sexual mode 

 of reproduction ; then the sexual organs, and the development and 

 structure of the second generation, ending with the structure and 

 germination of the spores. A new instance of vegetative budding is 

 described from the calyptra. 



In their genetic relationship, Goebel regards the Hepaticae and 

 Musci as two offshoots from the same stem, the lowest Hepaticae pre- 

 senting the nearest resemblance to the original stock. They may 

 possibly have sprung from the Thallophytes through Coleochaite, the 

 hibernating oospore of which presents no great diversity from the 

 sporogonium of Biccia. In the ascending scale the Muscineas have no 

 derivative forms, the series ending with them. 



Characese. 



Development of the Cortex in Chara.J — T. F. Allen employs 

 the mode of development of the cortex as a new basis for the classifi- 

 cation of the species of Chara, and distinguishes the following eight 

 methods : — 



1. Some species never develope cortex-tubes, and the stems remain 

 naked (C. coronata Ziz.). 



2. Some species develope a single cortex-tube, which is so small 

 that it does not join the one from the next leaf (C. inconnexa Allen). 



3. Some cortex-nodes develope spines, but no secondary tubes ; the 

 primary tubes join and completely encircle the stem (C. crinita 

 Wallr.). 



4. Some cortex-tubes show a partial development of secondary 

 tubes (C. evoluta Allen). 



* See this Journal, ii. (1879) p. 917 ; iii. (1880) p. 121. 



t Goebel, K., ' Die Muscinese.' Eucyklopaedie der Natuiwissenschaften, lte 

 Abtheil. 28 Lief. pp. 315-401. 



% Bull. Torrey Bot. Club, ix. (1882) pp. 37-47 (8 pi.). 



