558 



NATURE 



[Oct. 5, 1882 



soft. The colour of moistened specimens is of a sombre green, 

 inclining to olive. The trichomes, immersed in a homogenous 

 colourless jelly, spread themselves around a central space ; they 

 increase towards the periphery, and become lost in the interior. 

 These trichomes give origin to branches, either scattered or uni- 

 lateral, which elevate themselves to the one height and to hetero- 

 cysts either sessile on the side of the articulations, or borne on 

 a pedicel of one to three cells ; intercalary heterocysts were not 

 observed. The heterocysts were oblong in form, easily to be 

 distinguished from the ordinary articulations by their size, and 

 above all, by the nature of their contents, which is more horno- 

 genfous; when old, they assume a yellowish tint; the chloro- 

 iodide of zinc solution colours them purple. When an articulation 

 forms a heterocyst or a branch, it first forms a lateral 

 enlargement, which is very early isolated. This new cell 

 may at once change into a heterocyst, and then it will be 

 directly applied to the side of the articulation, as are the 

 heterocysts of Capsosira and those on the large branches of 

 Stigonema, or it may be divided once or twice before the forma- 

 tion of the heterocyst, which will be then pedicellated, or it may 

 even form the cell from which a branch may arise. The 

 branches, like the heterocysts, are not uniformly arranged along 

 the length of the filament. At certain intervals they become 

 closer and they become level at the same height. Some remain 

 simple, others ramify, none terminate in a hair. No distinct 

 trace of a sheath was observed around any of the younger por- 

 tions of the trichomes, but at the base the articulations are some- 

 times surrounded with a somewhat thick envelope. None cf 

 the specimens (not very numerous) examined showed the least 

 trace of spores or homogones. Two characters of this genus are 

 particularly interesting its Rivulariaceous appearance, and its 

 pedicellated heterocysts. This latter peculiarity, which to this 

 time was not yet met with among the Cryptophycece, indicates in 

 Mazrea a degree of specialisation of the parts of the trichome 

 more eminent than that in any other genus of Stigonemacete, in 

 fact represents the . highest development in the group. Now 

 that in this form and in Capscsira brebissomi = Stigonema zono 

 trichioides, Nordst, Stigonemacea? have Rivularioid represen- 

 tatives ; it maybe noted that Scytonemacese is the only tril .e in 

 which this type is wanting. The new species is beautifully 

 figured after drawings by Bornet (Bull, de la Soc. Bot. de France, 

 tome xxviii.). , 



Seed Leaves of Bursera.— The cotyledons of the natura 

 family Burseracea; are described by Bentham and Hooker 

 ("Genera Plantarum," vol. i. p. 321) as often membranous 

 contortuplicate, rarely solid and plano-convex, and in the genus 

 Bursera itself they are diagnosed in addition as " interdum 

 trifids, in una specie bippocrepiformes." Prof. Asa Gray, 

 [Free. Amer. Acad. Arts and Sciences, vol. xvii. p. 230) mentions 

 that specimens of Bursera microphylla were collected at Cape 



narrow linear lobes. The second pair are simpler, the secondary 

 lobes being fewer and short, the next succeeding are pinnately 

 parted into seven leaflets, passing toward the adult form of leaf, 

 which is pinnate with numerous very small leaflets on an inter- 

 ruptedly margined rachis. 



Affinities of the Bovver Birds. — The very interesting 

 group of birds known as the Bower Birds is regarded by Mr. 

 Elliott as connected with the Birds of Paradise, and in this view 

 Count Salvadori agrees. Mr. Sharpe in his "Catalogue of 

 Birds " takes a different view, but in a paper on the Ornithology 

 of New Guinea, ju-t published [Journal Linnean Society, vol. 

 xvi. p. 443, July 31, 1882), he acknowledges that he has now 

 been convinced that the views of Elliot and Salvadori are right, 

 and states that the following note, by Mr. Goldie, of the habits 

 of Diphyllodes chrysoptera, Gould, which is a true Bird of Para- 

 dise, has in great measure been the cause of this change of view. 

 Mr. Goldie writes : "The bird is found in very rough and thick 

 scrubby country, at the head of gullies or on steep sidings, where 

 he clears a space of ground, about seven feet by four, by 

 stripping all the leaves and twigs off the bushes, leaving only the 

 heavier branches. The ground is cleared of all leaves and is 

 quite bare, and this seems to be his playground ; in it he dances 

 and flutters about as if at play. The natives know his call and 

 attract him, but as soon as he perceives any one, away he flies, 

 and can be tempted no more at that time. When not about the 

 nest he is to be found in exceedingly high trees. His food 

 consists of seeds." These habits are curiously like those of the 

 Bower Birds, and show that Birds of Paradise can flirt on the 

 earth as well as among the tree tops. 



San Lucas, Lower California, 1 in fruit, and also in Sonora in 

 flower. It appears to have all the characters of Bursera except 

 that the ovules are solitary in the cells. Recently Messrs. Parish 

 have collected it in Arizona, near Maricopa, in fruit, and from 

 some of the seeds sent by them to the Botanic Gardens at 

 Harvard University, young plants have been raised. The 

 cotyledons are very peculiar, and are in the woodcut represented 

 a little larger than life ; they are biternately dissected into 



GEOGRAPHICAL NOTES 



Dr. Miklucho-Maclay has arrived at St. Petersburg after 

 a sojourn of twelve years on New Guinea and neighbouring 

 islands. It is stated that the eminent naturalist and explorer 

 intends to remain only six weeks in Russia, when he will return 

 to Sydney, where, as we have already intimated, he has been 

 the means of founding a zoological station. 



Dr. Emil Holub is arranging to set out for his new expedition 

 to South Africa in April 1883. He proposes to spend from six 

 to eight months in Cape Colony and in the Bechuana country 

 respectively ; alter which be intends to penetrate as far north of 

 the Zambesi as po-sible. Dr. Holub will devote his attention 

 to observations and collections in zoology, botany, geology, and 

 ethnography. 



Mr. H. K. Bancroft, author of the well-known work on 

 the Native Races of the Pacific States, is about to begin the issue 

 of a new work in 25 large vols., giving the History of the Pacific 

 States of North America. It is an enormous undertaking. 

 Triibner and Co. are the publishers. 



An expedition under Lieut. Andreyew, sent out by the Russian 

 Geographical Society, has safely reached Novaya Zemlya, where 

 it will pas^ the winter. Besides Litut. Andreyew there is a 

 scientific staff and five sailors. 



Mr. Stanford has issued the second instalment of Mr. 

 Ravenstein's large map of Eastern Equatorial Africa. It con- 

 tains sheets 12 to 18, with the exception of sheet 15. These 

 sheets combine all the region around Lake Tanganyika, a large 

 part of the course of the Lualuba, the Mwvtan Nzige, much 

 of the Victoria Nyanza and the country around it, and the wir'e 

 district lying between the north end of Nyassa, the south of 

 Tanganyika, and the coast to Zanzibar. The routes of all 

 travellers are given, the authorities for every leading feature 

 stated, and the information laid down so detailed that the map 

 serves all the purposes of a special treatise on African geo- 

 graphy. The map is a credit to Mr. Kavenstein as well as to 

 the enterprise of the Geographical Society, at whose expense it 

 is being constructed. ..a 



The Deutsche Rundschau fiir Geographic und Slatistii has 

 entered upon its fifth year, and appears to be a good example of 

 a popular journal of geography. In the first number of the new 

 volume we find an article on the Ethnography of Central Asia, 

 by Dr. Ujfalvy ; an article on Egypt, by Herr Schweiger- 

 Lerchenfekl ; an illustrated paper on Land and People in 

 Sikkim ; papers on the Transit of Venus and the Sun's Parallax, 

 by Dr. Haletchek ; on the Hydrography of Central Africa and 

 the interesting problem of the Welle, by Dr. Chavanne ; on 



