ZOOLOGY AND BOTANV, MICROSCOPY, ETC. 623 



will be seen that the formation of a piothallus in this case is preceded by a 

 very diflfcrent series of phenomena from those previously recorded. 



Structure of Davallia Mooreana.* — M. P. Lachmann states that the 

 horizontal rhizome of this fern is composed essentially of two vascular 

 bundles, which anastomose alternately right and left, and pass into two 

 dorsal rows of leaves. The supporting tissue is composed of fusiform 

 groups of fibres arranged irregularly round the conducting bundles ; these 

 fibres have their cavity filled with calcium oxalate, a peculiarity rare 

 among vascular cryptogams. 



Root of HymenophyllacegB.t — Contrary to the statement of Kussow 

 and Prantl, that there are always two vascular bundles in the root of 

 Eymenoplnjllum, and either one or more than two in that of Trichomanes, 

 M. P. Lachmann finds occasionally three bundles in the root of H. 

 demissuin, and always two in that of T. spicatum, radicans, and spinosum. 



Rliizodendron.| — Dr. K. G. Stenzel gives a minute description of 

 Bhizodendron Oppoliense, a fossil tree-fern from the cretaceous marl near 

 Oppeln. In close proximity to it are found also the remains of two other 

 tree-ferns with which it might easily be confounded, Protopteris fibrosa and 

 P. Cottaeana, which are also described. 



Muscinese. 



Protonema of Moss resembling Chroolepus.§ — Dr. A. Hansgirg believes 

 that many of the structures generally believed to be independent organisms, 

 and described under the names Trentepoldia, Chroolepus, and Gongrosira, 

 are in reality the protonemata of mosses. This is especially the case with 

 Chroolepus umhriniim, quercinum, and odoratum, and TrentepoMia uncinata 

 and lagenifera, and possibly also with C. iolithus and rupestre. He has re- 

 peatedly been able to trace the passage of the protonemata of mosses into 

 protococcus- and palmella-forms. In moss-protonemata closely resembling 

 T. lagenifera, he has been able to detect the development of zoosporangia 

 corresponding, in position and size, to the normal zoosporangia of this 

 alleged algti. 



Glistening Apparatus of Schistostega osmundacea. H — Dr. P. Vuillemin 

 graphically describes the life-history and habit of the moss Schistostega 

 osmundacea. In the deep damp fissures between stones the protonema 

 generation flourishes, and the sexual phase becomes rare. The histological 

 structure is briefly described. In specimens examined when fresh or after 

 being fixed with osraic acid, it is seen that all the chloroleucites are accumu- 

 lated in the protoplasmic mass at the posterior part of the cell, and there form 

 a continuous pigmented layer, on which the anterior lens of hyaline matter 

 concentrates the luminous radiations. As the incident radiation is diverted 

 from the optimum, the chlorophyll-bodies become disj)ersed in the parietal 

 protoplasm. The author describes the various arrangements of these bodies 

 in response to the varying intensity of radiation. The glistening protonema 

 can survive where the ordinary form would probably perish. Its propa- 

 gation is efi'ected by the stolon-like growth of the globular cells touching 

 the soil, or by the formation of actual conidial spores from the highest cells 



* Bull. Soc. Bot. Lyon, Avril 13, 1886. See Bull. Soc. Bot. France, ix. (1887), 

 Eev. Bibl., p. 3. 



t Ibid., Mai 11, 1886. See Bull. Soc. Bot. France, ix. (1887), Eev. Bibl., p. 3. 



X JB. Scbles. Gesell. vaterl. Cultur, Ixiii. (1886) 30 pp. and 3 pis. 



§ Flora, Ixx. (1887) pp. 81-5. 



II Jourii. Anat. et Physiol , xxiii. (1887) pp. 18-30 (1 pi.). 



