1868.] BRAITHWAITE— ORGANIZATION OF MOSSES. 463 



and hence often confounded them. His erroneous notion, that the 

 capsule was an anther, and the spores pollen, led his followers 

 astray, though we may chiefly attribute it to the want of sufficient 

 optical assistance. 



John Hedwig, however, now gave to the world those great 

 works which have rendered his mime immortal, and fully entitle 

 him to rank as the founder of Bryology. He was undoubtedly 

 the first to discover the sexual organs in these plants, and his 

 clear diagnosis of species is indicated by the great number which 

 still bear the names he imposed. 



These were followed by the valuable Bryologia Universa, and 

 other works of the learned Bridel, whose critical eye greatly 

 augmented the number of species ; and in our day Wilson, and 

 Mitten, and, lastly, Professor Schimper, have immensely extended 

 our knowledge of them, the Bryologia Europaea, of the last named 

 author, being the grandest contribution ever made to a single 

 department of botanical study. 



Bridel heads the first chapter of his Muscologia Recentiorum 

 with the querry, " Quid sit muscus?" (What may a moss be?;, 

 and this I hope you will be able to answer, after becoming 

 acquainted with the details of their structure. 



The mosses, to a cursory observer, may appear uninviting from 

 their minuteness and apparent similarity, yet when we call the 

 microscope to our aid, the exquisite beauty of their structure is 

 at once apparent. They are entirely cellular, and it is not surely 

 a subject for admiration, that by mere diversity in form, arrange- 

 ment, and construction of cells, we are able to characterize near 

 9,000 species in this one class of plants? 



The seed or spore— This is very minute, yet varying in 

 diameter between £ and T ±, of a millimetre; in some minute 

 mosses it is of large size, the capsule containing only ten or twenty 

 spores; in others it is very minute and innumerable. The spore 

 is globose, of a yellow, rufous, or brown colour; its surface smooth 

 or covered with rough points, and it consists of a mother cell, or 

 primordial utricle, enveloped in an outer coat, or exospore, the 

 contents being chlorophyl, starch, and oil globules, with mucus. 

 The first result of germination is the rupture of the outer coat, 

 and protrusion of the primordial utricle or cell, which immediately 

 commences division, the new cells repeating the process, until a 

 dense felt of branched confervoid threads results, which we term 

 the prothallium, and forming the green film we may often notice 



