QUEKETT MICEOSCOPICAL CLUB. 361 



bogs. In Wests' Monograpli sixty species and thirty-six varieties 

 of the genus Closterium are described. By the aid of photo- 

 graphs of specimens projected on the screen and drawings on the 

 blackboard, Mr. Wilson pointed out the distinguishing features of 

 some members of the genus. He said that the length and breadth 

 of the cell was an important feature in the determination of 

 the species, and that it was well to follow Wests' advice and 

 make careful drawings of any doubtful specimens. Mr. Wilson 

 concluded his remarks by expressing the hope that some of the 

 younger members of the Club would pursue the study of this very 

 beautiful and interesting family. A hearty vote of thanks was 

 accorded to Mr. Wilson. 



Mr. N. E. Brown described some " Imitative and Windowed 

 Plants." In 1811 Burchell, in his travels, states that he picked 

 up what looked like a curiously shaped pebble and found to his 

 surprise that it was a plant, which turned out to be a new species 

 of Mesembryanthemum — viz. M. turbiniforme. Burchell made 

 drawings, but collected no specimens, and nothing more was 

 seen of the plant for more than 100 years. Mr. Brown wrote 

 to various South African botanists with a view to obtaining 

 specimens, and in the autumn of 1918 Dr. Pole Evans, chief of 

 the Botanical Survey in South Africa, undertook to look for it. 

 He found the place where Burchell had seen it, and learned that 

 the inhabitants knew it as the " cow's-hoof plant." Eventually 

 a boy from a Dutch farm found him five specimens. Photo- 

 graphs of the plants growing in their natural surroundings were 

 shown on the screen : they were very difficult to distinguish from 

 the surrounding stones. Dr. Marloth has related how Mr. Ham- 

 mond Took was astonished to see yellow flowers growing on what 

 he had mistaken for pebbles on a piece of ground he crossed daily. 

 Which demonstates how closely these plants resemble the stones 

 they grow among. The plants have two leaves which are thick 

 and fleshy, and whose flat tops barely project above the ground. 

 Between the leaves is a cleft through which the flower grows. 

 In this country, owing to the lack of sun, the plant comes almost 

 out of the ground. At the base in the inside of the plant is a 

 bud which grows and eventually fills up the whole of the interior 

 of the fleshy leaves, absorbing their substance so that they dry 

 up to a mere skin, through which the new growth emerges, and 

 the skin is at last blown away. There is practically no chloro- 



