184 PROCEEDINGS OF THE 



fallen ; the President, who had arranged for the disposal of the 

 Library ; and Commander Spry, of Plymouth, who had gener- 

 ously sacrificed two days of his holiday to superintend the removal 

 of the library from 20, Hanover Square to the Museum. 



The Secretary read a letter from Mr. Lawrence thanking those 

 members who had taken part in the microscopical exhibition at 

 Roehampton House, and asking if it would be possible to arrange 

 another one. A letter was also received from Newbury Grammar 

 School asking if one of the members could give a lecture there on 

 the microscope or a microscopical subject. 



Mr. Morley Jones exhibited a specimen of Aulacodiscus grandis 

 (Walker and Chase), from Newcastle, Barbados, mounted to show 

 the girdle view of the valve, and described the method he adopted 

 for mounting heavy diatoms in such a position. A drop of thick 

 gum tragacanth mucilage is dried on a slip, the diatom is placed 

 upon it on edge, and the gum is breathed upon, so that the edge of 

 the diatom sinks into it as it is moistened. The diatom will prob- 

 ably fall over unless it has a flat edge, and must be rearranged with 

 the bristle while the gum is moist. When the attached edge is 

 well embedded in the gum it must be breathed upon again, and 

 the diatom supported with the bristle in the desired position until 

 the gum dries. The diatom must then be examined with a high 

 power (1/6 in.), and if not straight the operation must be repeated. 

 The cover-glass should be supported on three pieces of cover-glass 

 of suitable thickness. If the above method fails, the diatom 

 may be gummed against the edge of a piece of cover-glass fixed 

 on the slip, and the cover supported as before on pieces of cover- 

 glass just thicker than the diameter of the diatom. 



Dr. J. Eudd Leeson then gave an account of the Tooth- 

 wort {Lathrea squamaria). It was, he said, one of those plants 

 that one hears about all one's life and never sees. He had known 

 of it for forty years, but never seen it until quite recently. The 

 plant when fresh is white and fleshy, but it turns brown when 

 preserved in spirit. It has received the name of toothwort from 

 the tooth-like shape of its leaves, and its generic name, Lathrea, 

 is derived from the Greek \d6po<;, meaning " hidden," as the plant 

 grows hidden among dead leaves and loose earth. It is allied to 

 the broomrapes. The plant is perennial, and sometimes covers 

 areas of a square yard ; it is destitute of chlorophyll, and is a 

 parasite on the roots of hazels, elms, beeches, etc. It lives in 



