ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 481 



allied to B. pendulum as indicating best how the external and internal 

 peristome of the Bryaceae represent, the one by its ventral, the other 

 by its dorsal plates, the divisions of one and the same layer of cells 

 analogous to that which composes the teeth of Splachnum. 



Abnormal developments in the Capsule of Mosses.* — Dr. K. M. 

 Gottsche describes the following examples of abnormal development, 

 viz. — (1) Two stems of Polytrichum gracile, with the setse perfectly 

 distinct, and the capsules covered by a common bilocular calyptra; 

 (2) P. juniperinmn in which the seta perforates the calyptra, and 

 bears at its summit the fully developed capsule ; (3) several examples 

 of Bryum pseudotriquetrum with two or three capsules developed on one 

 seta. The first abnormality results from two perfectly distinct 

 archegonia, the hairy coverings of which (found in Polytrichum and 

 OrthotricJium only) have become united in their growth. 



Fructification of Didymodon ruber.f — M. Philibert has for the 

 first time met with this alpine moss in fruit. It is strictly dioecious, 

 the male and female plants forming separate tufts. M. Philibert 

 recognizes in the Barbulacero a progressive evolution of the peristome, 

 the extremes of which are represented on one side by Barbula, on the 

 other side by Pottia, and of which the genera Didymodon, Desmatodon, 

 and Trichostomum are intermediate terms. Didymodon rubellus and 

 ruber represent two degrees of this evolution, which, starting from the 

 structure common to the Aplolepideas, reaches a very special type ; the 

 peristome of D. rubellus approaching more nearly the type of Pottia, 

 that of D. ruber the type of Trichostomum. 



Scandinavian species of Orthotrichum and Ulota. J — In a mono- 

 graph of the Scandinavian species of these genera based on the work 

 of Venturi, Herr A. L. Gronvall describes seven new species. 



Regeneration of the Marchantieae. § — Dr. H. Vochting has made 

 a series of observations of the vegetative power of reproduction dis- 

 played by the thallus of the Marchantieje, using as his subject chiefly 

 Jjunularia vulgaris. 



The author distinguishes, in the first place, between organs with 

 unlimited and those with limited power of growth, among the former 

 being the thallus. By making sections of this in various directions 

 he concludes that the new formations always arise on what is morpho- 

 logically the under side, usually from the tissue of the mid-rib, and 

 grow in the direction of the apex. This differentiation of upper 

 and under side is not, however, dependent on the position of the 

 shoot, nor on the relative illumination, but, according to the experi- 

 ments of the author, on internal causes dependent on the organization 

 of the thallus. Isolated masses of cells possess this faculty of new 



* SB. Gesell. Bot. Hamburg, Jan. 29, 1885. See Bot. Centralbl., xxv. (1886) 

 p. 224. 



t Rev. Bryologique, xii. (1885) pp. 89-94. 



X Arsberatt. Malmo allm. laroverk, 1885, pp. 1-25 (1 pi.). See Bot 

 Centralbl., xxiv. (1885) p. 3. 



§ Priugeheim's Jahrb. f. Wiss. Bot., xvi. (1885) pp. 367-414 (4 pis.). 



