Miscellaneous. 355 



same form, but their structure is the same, or at least appeared to 

 me to be so. They are wedge-shaped or parallelogrammic, about 

 y^ths of a milHmetre in length, and from y^ths to yfo^hs in breadth. 

 It is very difficult to ascertain their thickness, but I believe it to be 

 about a third of their length. They are composed of at least two 

 layers of two or three rows of broad cells on either surface, as vi- 

 sible under the microscope. Their colour is a deep green verging 

 on bistre. I know of nothing at all similar in the family of Mosses, 

 and at least in a physiological point of view, the fact is not unim- 

 portant. It must be observed that the capsules were quite ripe, 

 having already lost their opercula, so that the question is not one of 

 unripe spores. The species in which this curious structure was ob- 

 served is Eucamptodon perichcetialis, Mont." 



Dr. Montague kindly accompanied his observations with speci- 

 mens, which has enabled me to confirm their correctness. — M. J. B. 



M. Agassiz on the Geological Development of Animal Life. 



The Zoophytes, Mollusca and Articulata existed in the earliest pe- 

 riod of the earth's development, although all their classes were not 

 numerously represented in the oldest members ; but they do not al- 

 low of our supposing that any progressive perfection to the present 

 creation occurred. This is the case with the Vertebrata only, among 

 which fish appeared in the first period, reptiles in the second ; mam- 

 malia and birds did not appear for a long time after the former ; lastly 

 came man, as lord of all : hence M. Agassiz denominates the corre- 

 sponding periods, those of fish, reptiles and mammalia. 



The greatest change in the fish occurred at the end of the Jura 

 period. All fish which existed prior to the chalk have a peculiar 

 aspect and belong in general to extinct families ; those of the later 

 epochs resemble those now living, and many of them belong to fa- 

 milies and genera at present in existence ; but they all differ speci- 

 fically, just as all Vertebrata in different geological epochs differ in 

 species. — Jahrhuch fur Mineralog. Geolog. &c.. Part 3. 1845. 



EXPLORATIONS OF DR. SCHRENK. 



The extreme limits of the wild and remote regions of south-eastern 

 Siberia and along the Chinese frontier have been successfully ex- 

 plored by an able and enterprising botanist. Dr. Schrenk, who has 

 recently returned to St. Petersburg. Remote and unfriended, this 

 ardent naturalist has passed four years in a country, the greater part 

 of which was never before trodden by an European foot. In addition 

 to copious materials with which he will soon enrich botany, geology, 

 and other branches of science, he has made most important obser- 

 vations on the eastern extension of the mass of land which forms a 

 portion of that vast depressed area so vividly brought before our con- 

 sideration by Humboldt, and which is now found to extend eastward 

 from the shores of the Aral to the Saissar and Balkash lakes ; though 

 in approaching the latter region the ground rises to a few hundred 

 feet above the sea. Thence penetrating to the lake of Issikul, sur- 

 rounded by lofty mountains considerably south of the range of tlie 



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