ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 781 



B. CRYPTOGAMIA. 



Cryptogamia Vascularia. 



Anatomy of Vascular Cryptogams.* — P. Van Tieghem has 

 studied several points in the anatomy of vascular cryptogams, recent 

 and extinct. The secondary tissues of cryptogams, like those of 

 phanerogams, proceed normally from two concentric generating 

 layers ; an external one in the cortex, forming bark outwardly, and 

 secondary cortex inwardly; an inner one in the central cylinder, 

 intercalated in the liber and in the xylem of the primary vascular 

 bundles, producing secondary liber outwardly, and secondary wood 

 inwardly. The normal subero-cortical generating layer is well de- 

 veloped in the stem (BotrycMum, Helminthostachys), root {BotrycMum, 

 HelminiJiostachys, Angiopteris, Marattia), and leaves {BotrycMum, 

 Angiopteris, Marattia). The normal libero-ligneous generating layer 

 is developed both in living ferns {BotrycMum, &c.) and in extinct 

 vascular cryptogams, as Splienophjllum and Sigillaria. In addition 

 to these normal layers we find in certain species two other abnormal 

 generating layers : one external to the primary vascular bundles 

 {Isoetes), and one interior to the primary vascular bundles {Botry- 

 cMum). 



The author also describes several anomalies in the primary 

 structure of the root, viz. in the principal trunk and in the branches 

 of a dichotomous root. 



Fertilization of AzoUa.f — E. Eoze has studied the structure of 

 the androspores (microspores) and gynospores (macrospores) and the 

 mode in which fertilization is effected in Azolla filiculoides, but 

 without adding anything fresh of importance to what is already 

 known. He observes that the barbed hairs attached to the " massulfe " 

 as they escape from the androsporangium do not occur throughout 

 the whole genus, being wanting in Azolla pinnata and nilottca. The 

 internal membrane of the gynosporangium, which remains attached 

 to the gynospore in the form of a funnel, appears to play an important 

 part in fertilization in facilitating the access of the antherozoids. 



J/LvLBcineee. 



Male Inflorescence of Mosses.:}: — H. Satter confirms the observa- 

 tions of Leitgcb and Kiihn in the case of Fontinalis and Andrecea, that 

 the axil of the shoot is used up in the formation of the antheridial 

 receptacle, Leitgeb regarding this to be the rule with mosses. The 

 author shows that this is also the case with many BryincfB, also 

 with Phascum and ArcMdium, which display apparent exceptions to 

 the rule. 



In Phascum cuspidatum the last three segments and the apical cell 



* Bull. Soc. Bot. Franco, xxx. (1883) pp. 169-80. 



t Ibid., pp. 198-200 (1 iii^.). 



X Btr. DeutMcli. Bot. Getjcll., ii. (1884) i)p. I3-'J (1 pi.). 



