538 SUMMARY OF CUKEENT RESEARCHES RELATING TO 



a hadrome. The " leptome " is the part of the bundle which contains 

 albumen, and is composed therefore of sieve-tubes and cambiform, 

 understanding by the latter term the elongated parenchymatous cells 

 which accompany the sieve-tubes and contain nothing but albumen. 

 The " protophloem " or " protoleptome," consisting, in Dicksonia 

 antarctica, of sieve-tubes, must apparently be included here. The 

 " endodermis," whose function appears to be purely mechanical, and 

 the starchy layer adjoining it on the inside, proceed from a common 

 histogen, the " coleogen." In the young leaf-stalks of Dicksonia 

 antarctica there is a gradual transition from fundamental parenchyma 

 through the coleogen to the procambium. In many rhizome-bundles 

 the coleogen is in immediate contact with the protohydrome. 



The rhizome-bundles of the Polypodiaceae are stated to be not 

 concentric, but bicollateral. 



The following is a table of synonymous terms. 



f Sieve-tubes . . ] 

 Phloem .. .. . \ (Protoleptome) .. i Leptome 



[ Cambiform .. ) } Mestome. 



Xylem I Hydrome .. •• 1 Hadrome 



^ \l Amylome .. -. J 



j Endodermis. 

 Fundamental Tissue j Stereomc-sheath 



\ and adjuncts. 



Muscinese. 



Anatomical Structure of Mosses.* — G. Firtsch describes the 

 mechanical contrivances in the anatomical structure of the following 

 parts of the moss Polytrichnm juniperinum : — the mechanical system 

 of the stem and seta ; the firmness of the steroids ; the mechanism of 

 the unrolling and erecting of the leaf; the contrivances for fixing 

 the sporogonium in the stem ; and the hairy covering of the calyptra. 



Hybrid Moss."]" — H. Philibert records a new instance of a hybrid 

 moss, found wild, between Orthotriclium diaplianum and 0. Sprucei. 

 He considers it a true instance of a hybrid sporogonium, resulting 

 from the fertilization of an archegonium of 0. Sprucei by antherozoids 

 of 0. diaphanum. The hybrid was intermediate in its characters 

 between the two parents, and also in the time of producing its repro- 

 ductive organs. 



Fungi. 



Localization of the Hymenium of Fungi.J — N. Patouillard 

 inquires why, if all the hypha3 of a fimgus are morphologically equi- 

 valent, the hymenium is as a rule localized to the under side of the 

 pileus, where it is not unfrequently renewed after having been once 

 destroyed. He believes the reason to be that the under side of the pileus 

 is the best protected part of the structure, and enumerates instances 



* Ber. Deutsch. Bot. Gesell., i. (1883) pp. 83-97 (1 pi.). 



t Key, BryoL, x. (1883) pp. 8-13. 



t Rev. Mycol., v. (1883). See Bot. Centralbl., xiv. (1883) p. 130. 



