8 PUOCEEDINGS OP THE 



Miss May Eathbonb, P.L.S., exhibited an Acorn producing 

 twill plants, tlie two steins showing great diiferences in colour ; 

 the plants had been grown in water, as shown. 



Dr. Eendle and Mr. W. C. A\''orsdell commented on this 

 exhibition. 



Mr. E. S. GooDEicn, F.E.S., Sec.L.S., showed the Winter and 

 Summer coloration of the Ermine, Putorms ermhieus. He spoke 

 of the various theories which had been suggested as the cause of 

 this change, and dwelt upon that proposed by Metschnikoff, that 

 phagocytes advanced up each hair as the effect of some stimulus, 

 and destroyed the pigment, reducing the hair to white. 



The President, the Eev. T. E. E. Stebbing, Mr. A\^ C. AVorsdell, 

 and Dr. A. P. Young discussed the phenomenon, and Mr. Goodrich 

 replied. 



The last paper was by Mr. E. P. Stebbixg, " The Infestation of 

 Bamboos in Tidal AVaters by Balanus amj^hitrite and Teredo 

 navalis in Tenasseriui." In the absence of the author this was 

 epitomised by the Zoological Secretary, who stated that the rapid 

 destruction of bamboo piles was a serious loss, and the investiga- 

 tion showed that up to now no species of bamboo is immune ; 

 research is to bo continued. 



March 2ud, 1916. 



Prof. E. B, PoLLTON, E.E.S., President, in the Chair. 



The Minutes of the General Meeting of the 17th February, 1916, 

 were read and confirmed. 



Dr. James Charles McWalter was proposed as a Eellow, and 

 Prof. Henri Lecomte, Paris, Prof. Edmond Perrier, Paris, and 

 Prof. Pier' Andrea JSaccardo, Padua, as Foreign Members. 



Mrs. Elsie AVilkins Sexton was elected a Fellow. 



Dr. Annie Porter, F.L.S., exhibited preparations of the 

 diarrhoeic stools of soldiers from Flanders, wlio were infested 

 with Giardia {Lamhlia) intestinalis, a Protozotin possessing two 

 nuclei, eight tlagella, and two axostyles, as well as a sucking-disc. 

 The patients in each case had never been abroad until they weut 

 to Flanders, where the diarrhcjuic conditions were contracted. 

 Blood was sometimes voided with the faeces, suggesting the 

 presence of intestinal ulcers, as Lamhlia occurred in the stool- 

 blood. The infective stages or cysts of the parasite are ovoid 

 bodies, about 10 /x to lb fx by 7 ^ to 9)u, containing two or 



