1869.] Botamj and Vegetable Fhysiohgij. 523 



horizon; to 0"*80 at an elevation of 25° ; to 0"*95 at an elevation 

 of 15°; l"-20 at 10°; l"-92 at 5°; and, finally, 3" -32 at 3^ above 

 the horizon. These results are of the utmost importance in relation 

 to the probable correctness of the proper motions assigned to stars 

 which do not rise high above the horizon of Greenwich. 



Mr. Browning describes a remarkably simple form of star-spec- 

 troscope. It is for direct vision, and weighs only about 7 ounces, 

 or much less than an ordinary micrometer, so that it will scarcely 

 at all affect the balance of a telescope. 



4. BOTANY AND VEGETABLE PHYSIOLOGY. 



The Antheridia of Ferns. — Dr. Kny, of Berlin, records some inter- 

 esting observations on the development of the Antheridia in Ferns, 

 which has hitherto received several distinct explanations, in spite of 

 its apparently simple character. CeUs of the form of closed rings 

 have hitherto been observed only in the full-grown frond of several 

 species of Aneimia. Concermng the mode of their formation there 

 is a difference of opinion, at present unreconciled, between Hilde- 

 brand and Strassbm-ger ; but both these authorities agree in this, 

 that the ring-cells have not been originally produced as such, but 

 have received their pecuhar form as a secondary development. In 

 the antheridia of some species of Polypodiacese and tSchizseaceai, Dr. 

 Kny has observed, as he thinks, the first example of a direct origin 

 of ring-cells by the formation of funnel-shaped separating walls. 

 They show at the same time that this occurrence, hitherto enthely 

 isolated in the vegetable kingdom, admits of two modifications; 

 since the ring-cells are separated in the one case from a hemisphe- 

 rical, in the other case from a bell-shaped^ mother- cell. Dr. Kny 

 promises further researches in this interesting field. 



Bep'oductive Organs of Lichens. — According to M. Famitzin, 

 the Gonidia of Lichens — that is, the spherical cells filled with chlo- 

 rophyll which are dispersed in the parenchyma of the frond — if 

 maintained in a condition of sufiicient humidity on the surface of 

 bits of bark during several months, will give rise in their interior to 

 zoospores; that is, to uniform corpuscles provided with definite 

 movements by vibratile ciha hke the zoospores of Algae. 



Specfroscojnc Examination of Diatomaceie. — Mr. H. L. Smith* 

 has confirmed the vegetable nature of Diatoms by the apphcation 

 of the spectroscope. He has proved the absolute identity of chloro- 

 phyll or the green endochrome of plants, with diatomin or the olive- 

 yellow endochrome of the diatoms, by the identity of their spec- 

 trum, which is a very remarkable one. 



* ' American Journal of Science and Arts.' 



