Micro-photograpli of St. Sulspice, Paris Robert Nicholson. 



Micro-photograph, page of the Times J. M. Williams. 



Micro-photographs, various F. T. Paul, F. R. C. S. 



Do. J. H. Clayton. 



Slides recently added to the Cabinet Alfred Leicester. 



May 7. — The President delivered an address entitled "Remarks on Melobesia 

 and its Allies," which was illustrated with diagrams and a beautiful 

 series of calcareous seaweeds, from the small forms on our own 

 coast to the tinted corallines of California, including also a large 

 mass of white stony carbonate of lime, which was once a plant 

 growing on the sea bottom. These plants form a division of the 

 algffi, having a rigid stem ; nearly all found in salt water, and in 

 almost every latitude. These hard shelled seaweeds differ physio- 

 logically from their softer kinsmen, and thus there ensues a 

 morphological difference. The relationship existing between the 

 giant Scquoida Wcllingtonia of America, which towers to a height 

 of 300 or 400 feet, and the tiny crisp seaweed, is not superficially 

 apparent, but it exists nevertheless. The calcareous seaweeds are 

 near relatives of the deep-water weeds, but as they came near the 

 shore, where the waters dashed and roared, then came a necessity 

 for a harder coat than when in the quiet waters of the deep, and so 

 they learned to secrete an armour of carbonate of lime. This stiff, 

 brittle, stony matter would not have helped them at all, unless it 

 had been modified to elasticity, and this is admirably shown in 

 the "shepherds' purse coralline, " where the armour is in short, solid 

 joints, forming little triangles, with the apex downwards, so that 

 each joint moves freely on the part below it, thus forming a strong- 

 jointed armour for the delicate plant body. The massive lime-like 

 form of the Mclohesia is simply a modification of this same process, 

 by which the tender seaweed has found jirotection from the 

 dashings of the sea. This development has doubtless occurred in 

 past times, but the modified stability of species keeps them all 

 true to their form. The number and variety of the seaweeds are 

 enormous, but as they have not hitherto been of great economic 

 importance, they have not received the study they deserved ; but 

 they are an exceedingly interesting group. During Professor 

 Hooker's researches into Antarctic flora and fauna he discovered 

 the famous seaweed which, from the one stem, has floating fronds 

 over 1000 feet long, in which countless forms of life find food and 

 shelter. The lowly seaweed thus becomes to the plant family what 

 the whale is to the mammals — the overshadowing form of all. 



