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ultimate ramuli short, linear, subulate, and so closely set that their 

 slightly expanded bases touch each other, longest below the middle of 

 the pinnule, giving it a lanceolate or ovato-lanceolate outline ; all the 

 divisions except the last are of very unequal length and ramification, 

 one being scarcely a line in length, and scarcely pinnate, while the one 

 by its side is two or even foiu- inches long and tripinnate. Favellae 

 clustered at the apex of short stalks formed from metamorphosed abbre- 

 viated ramelli, with which they generally alternate, but not unfrequently 

 the whole or most of the ramelli are fructiferous, and occasionally favella3 

 are produced on most of the ramuli, even down to the third or second 

 series ; the cluster is surrounded by from six to eight subulate invo- 

 lucral ramuli, about three times the length of the cluster. Tetraspores 

 roundish, triparted, seated on minute pedicels which fringe the margin of 

 slightly abbreviated pinnules. Structure consists of a single articulated 

 thread, composed of joints rather longer than broad, surrounded with 

 a thick stratum of minute cells, intersjiersed with others very large, 

 ovate-oblong, all filled with granular endochrome, those at the surface 

 coloured. Substance cartilaginous, generally adhering to paper in drying. 

 Colour, a deep somewhat brownish red, changing to yellowish green in 

 decay. 



This beautiful Alga is one of the most common sea-weeds on the 

 shores of Scotland, both on the east and west coasts. On the northern 

 shores of England it is of less frequent occurrence, and becomes less 

 and less common as we proceed southwards, and on the southern shores 

 entirely disappears. Delighting in low temperatures, however, it extends 

 the range of its habitat even to the shores of the Arctic Ocean, and 

 is said to be equally abundant both in the North Atlantic and in the 

 North Pacific, thus occupying a broad zone of latitude which encircles 

 the world, only interrupted by the land and the depths of the ocean 

 on either side. 



It is curious and highly interesting to study the laws that regulate 

 the distribution of plants. The distribution of land plants must always 

 be circumscribed, and even of those less likely to be afifected by any 

 slight change of temperature, must proceed slowly ; but that of sea- 

 weeds should be under no such rigoroiis restraint, yet it seems regulated 

 by laws as strict and unvarying. Why should not the present species 

 be found on our southern as well as on our northern shores 1 The chalk 

 cliffs of England cannot deter it, as it lacks the wisdom of the wise 

 man to fix its home upon the rock ; the stems of Laminaria digitata, 

 its chosen habitat, are not wanting even on the shores of France and 

 Spain, and its spores must be often carried by the tide as far, and scat- 

 tered in myriads on these distant shores, yet there they have ceased 



