436 



NATURE 



[Sepi. 20, 1877 



Society, under the name of Coleine. Colourless glands 

 become coloured artificially after the absorption by 

 the leaves of red-stained albumin. The fibro-vascular 

 bundles, as far as the petiole, are also coloured, thus ren- 

 dering the absorption very evident. After death black 

 granules form in the tissues of the leaf, visible as black 

 specks on the surface. 



In the midrib of the petiole a well-developed axile fibro- 

 vascular bundle runs ; from it straight branches proceed 

 into the wings in a " curved veined " manner. The 

 branches split into smaller and smaller twigs, the branch- 

 ing, however, not being symmetrical. In the midrib of 

 the lamina there is a large axile fibro-vascular bundle, 

 which gives off branches (at a right angle) running parallel 

 towards the margin, where they fork and again unite. 

 One bundle formed by the union of the fork-branches 

 runs into each marginal seta of the leaf. 



The phloem of the fibro-vascular bundle consists of 

 soft bast ; the xylem, in the lamina, chiefly of spiral 

 vessels ; in the petiole there are other vessels in addition. 



In the youngest leaves the petiole and lamina are not 

 separable. The part first formed, and springing from the 

 flat vegetative cone represents the origin of the lamina, 

 but it remains rudimentary for a long time, during which 

 the petiole is rapidly developing at its base. The lamina 

 at first forms a straight continuation of the stalk, then 

 bending through an angle of iSo° bends itself over into 

 the grooved petiole. Afterwards it just reverses the pro- 

 cess and straightens itself as it expands. 



The margins of the lamina are in the early stages rolled 

 inwards. Afterwards the petiole expands in a plane, and 

 last of all the lamina becomes fully developed. 



The stem is short and thick v/ith a ring of xylem. The 

 bundles pass transversely, so that one enters each leaf 

 and each root. 



The lateral rootlets are long and strongly developed, 

 but never branch. The cells at the apex are red in colour, 

 the cortical cells become brown in centripetal order and 

 die in as far as the sheath of the fibro-vascular bundle. 

 The vessels develop first at the periphery of the axile 

 bundle, increase in a centripetal direction, and ultimately 

 form an eight-rayed star. 



The third paper is by Dr. J. Schroeter, " On the Deve- 

 lopment and Systematic Position of Tulostoma, Pers." 

 It describes the structure of a very interesting little fungus 

 which passes part of its life below ground, then the stalk 

 elongates, and the open periderm, with a capillitium, appears 

 above ground. The plant described is Tulostoma pedun- 

 ciilatuin, L. {T. linunale, Pers., T. mammosiim, Fries. 

 Cooke). The sporocarps are developed at a depth of 

 from two to three centimetres below the surface of the 

 ground. They spring from a white, branched, thread-like 

 mycelium, running between grass-roots, and old moss- 

 plants. The mycelium gives rise to fusiform structures of 

 varying thickness, and these pass over by all gradations 

 into true scleroiia. The sclerotia give rise to the sporo- 

 carps, but the development was not observed ; apparently, 

 however, they bud out from a spot on the surface of 

 the sclerotium. At first the sporocarp is like a small 

 bovista. The spores are developed on remarkable basidia. 

 These form four elongations springing from the sides at 

 unequal heights, and each develops a spore. The basidia 

 only last a short time, and a capillitium is developed in the 



interior of the peridium, the spores lying between the 

 meshes. Tulostoma has been placed among the Gastero- 

 mycetes,in the Lycoperdacea;,but the peculiar development 

 of the basidia at once separates it from the Lycoperdacca;, 

 and Schroeter proposes to place it in a new group of the 

 Gasteromycetes, the Tulostomaceas. The curious genus, 

 Pilacre, seems also to Schroeter to belong to the same 

 division, and he further suggests the possibility of the 

 remarkable genus Batarea being also related. 



The fourth paper is one of the highest interest and 

 deals with a most remarkable group of plants. Exceed- 

 ingly simple in structure, they attack many alg;E and 

 water-plants, and seem not unfrequcntly to have been 

 described as the fruits of alga; by certain algologists. It 

 is by Dr. Leon Nowakowski : " Contributions to the 

 Knowledge of the Chytridiacete," and is illustrated by 

 three plates. The genus Chytridium, which gives its 

 name to the group, consists of only one cell. Rhizidium 

 consists of two cells, the lower forming a root-like or 

 branched mycelium-like structure, while Synchytrium 

 consists of a group of cells. Zygochytrium and Tetra- 

 chytrium of Sorokine are the most highly developed, and 

 in them the zoosporangia are produced as a branched 

 bearer. Nowakowski describes a new genus, Cladochy- 

 trium, in which a branching mycelium is developed in the 

 tissues of the host-plant. Another new genus, Obelidium, 

 has a stalk to the zoosporangium and a well-developed 

 mycelium. The spores of Chytridium are formed by free- 

 cell formation in the zoosporangium, and generally possess 

 a very highly refracting nucleus. The zoospores exhibit, 

 as first pointed out by Schenk, peculiar amoeboid modifi- 

 cations of form. The zoospores have only one cilium 

 either before or behind. Conjugation of zoospores has 

 not been observed. When the spores germinate the 

 nucleus gradually disappears and the whole spore either 

 at once grows into a new zoosporangium, or a sort of 

 mycelium is formed. Resting spores have been observed 

 in Chytridia as in Rhizidium, and probably occur in 

 others. The position of these plants is at present doubt- 

 ful, but probably they are allied to Saprolegnia. 



Nowakowski has described certain new forms and 

 carefully- observed forms already described but not fully 

 studied. The following is a synopsis of the forms 

 described : — 



I. Chrytidium, a. Br. 



1. C. destruens, nov. sp., occurs in cells of a new green 

 gelatinous alga, developing zoospores, and described by 

 Nowakowski under the name of Ciicetoiieiiia iyregulwe. 



2. C. i^regariuin, nov. sp., in the ova of a Rotifer ; 

 found among the gelatinous matter of Clicetoplwra eiidi- 

 vicefolia. 



3. C. macrosporum, nov. sp., also in the ova of a Ro- 

 tifer ; found among the gelatinous matter of Chcetophora 

 eU'^ans. 



4. C. coleocliaetes, nov. sp. In the oogonia of Coleo- 

 cliaete puhnratum, and never in the vegetable cells. 



5. C.microsporuin, nov. sp., a specimen ai Mastigothrix 

 (xruginea, Ktzg., found in gelatinous matter of Chatoplipr<i 

 elegans. 



6. C. epithemia, nov. sp., an Epitliemia zebra, one of 

 the Diatomaceaj. 



7. C. mastii^otriehis nov. sp., a mastigothrix ceru- 

 s^inea, as in No. 5. 



II. Obelidium, nov. gen.. Now. The one-celled zoo- 

 sporangium is elevated on a more or less developed bearer 



