620 SUMMARY OF CURRENT RESEARCHES RELATING TO 



tlio name of aspidol ; it Las the compositiou CzoHj^O, and is iusoliiblc in 

 alkalies, but easily soluble in other, benzene, cbloroform, light petroleum, 

 and hot alcohol. 



Selaginella lepidophylla.* — M. Lcclerc du Sablon describes the 

 curious jiropcrty of revivification possessed by Selaginella lepidophjlla. 

 When the root withers, each branch curls up, and the plant appears 

 more or loss in the form of a ball. In this state it is able to remain for 

 a long time ; and then, when the water necessary for its growth is supplied, 

 the branches unroll, the green color which had almost disappeared 

 returns, and the branches and roots recommence to grow. The structure 

 of the plant is such that when dehydration occurs, the cells on one sido 

 of a branch are thicker than those on the other, thus they contract 

 unequally and cause the branch to curl up. 



Solms-Laubach's Introduction to Fossil Botany. j — This valuable 

 work is devoted chiefly to the remains of Vascular Cryptogams, no 

 reference being made to Angiosperms, and a small portion only of the 

 space being devoted to Thallophytes, Musciuefe, and Gymnosperms. 

 Besides the organisms of doubtful position, he classifies the fossil 

 Vascular Cryptogams under the following heads, viz. : — Ferns, Equise- 

 tacete, Hydropteridete, Lycopodites and allied forms, Lepidodendrea3, 

 Sigillariea3, Stigmaria, Calamarieae, and Sphenophylleae. The Leioder- 

 mariefo are regarded as belonging to the Sigillariefe rather than to 

 Gymnosperms. The Calamarieae are treated as belonging to a difibrent 

 section to the true Equisetacete, and as having been furnished with both 

 macrospores and microspores. 



Muscineae. 



Peristome of Mosses.| — Continuing his observations on this organ, 

 M. Philibert now especially deals with the structure of the internal 

 peristome and its variations. The internal peristome of the Ortho- 

 trichefe is not very dissimilar from that of Neckera, Wehera acuminata, 

 Cylindroihecium, and the other Hypnobryaccje, where the basilar mem- 

 brane is very short. The primitive rosette is always composed, on the 

 dorsal surface, of sixteen rows of rectangles opposite to the ventral 

 plates of the teeth, and on the ventral surface, of less regular trapezes 

 forming fewer rows. This structure of the internal peristome is not 

 essentially different from that of the Bryaceas. In the genus Cinclidium 

 the internal peristome presents a somewhat singular aspect. It has the 

 form of a cylinder closed above by a hemispherical dome. The lower 

 half has the same appearance, the same colour, and the same structure 

 as in the genus Mnium. The only difference between the structure of 

 the internal peristome in the Cinclidieje and the genus Mnium is that in 

 the former the thickening extends all over the surface of the peristomal 

 cylinder. In the Fuutinalacefe the internal peristome has the form of 

 an elongated cone, composed of sixteen straight, vertical filiform columns, 

 which are connected by numerous equidistant horizontal branches. 

 Cinclidium suhrofundum forms a connecting link between the structure 

 as found in the Cinclidiea) and that of the Fontinalacea3. 



* Bull. Soc. Bot. France, xxxv. (1888) pp. 109-12. 



t Solms-Laubach. H., Graf zu, 'Einleitung in die PaljEophytologie,' 416 pp. and 

 49 figs., Leipzig, 1887. 



X Rev. Bryol., xv. (1888) pp. 24-8, 37-44. Cf. this Journal, ante. p. 461. 



