91 



Mr. A. D. Michael having taken the chair pro. tern., 



The President read a paper " On Human lilaricB,'' which he illustrated 

 bv numerous diagrams and by specimens exhibited in the room. 



Dr. Matthews said he should like to ask Dr. Cobbold a question. Some 

 years ago there was an invasion of mosquitos m some parts of London; 

 they were supposed to have been brought over by some ships. Some ob- 

 servers examined them and declared that they did not present any features 

 to distinguish them from the ordinary gnat. He should like to ask if there 

 was any difference between the two? Also, he should like to ask what 

 became of the Filarics which were swallowed by the mosquitos ? 



Dr. Stephen Mackenzie said he had a case now under treatment in the 

 London Hospital, and that he had repeatedly examined the blood during the 

 afternoon, but found no Filarics whatever. At Dr. Cobbold's suggestion he 

 had also examined the blood at midnight, but found none then. In another 

 case of Elephantiasis the worm had been found in the scrotum, but not in 

 the blood. He thought the facts stated were of great importance, although 

 lie believed that they had not any cases in which the Filarics had survived 

 the journey to this country. All the cases of Elephantiasis which had come 

 under his notice were imported cases from tropical climates. 



The President said that it had not occurred to him to look into the 

 question of the species of mosquitos, but he believed that Westwood ad- 

 mitted that nearly all the species of mosquito were reducible to two types, 

 although as many as twenty species had been spoken of. As to what 

 became of the Filarics after they had been swallowed by the insects, it was 

 only the female mosquito which attacked man, and as she died after deposi- 

 ting her eggs upon the water, the Filarics passed into the water. Accord- 

 ingly, when the natives drank the water in an unfiltered condition, the 

 parasites were taken into the stomach, and made their way thence to the 

 lymphatics and neighbouring tissues. He was very glad to see that the 

 practical importance of the matter commended itself to the judgment of Dr. 

 Stephen Mackenzie, but was not surprised to find that he did not know any- 

 thing of the peculiarity or periodicity in the habits of Filarics, because it 

 was an entirely new fact. The capacity of this entozoon for producing those 

 diseases ascribed to it, was a matter which would of course be fought and 

 battled over for many years to come. 



Dr. Matthews said he should like to know if anyone had been able to con- 

 nect the periodicity of the parasites in the blood with the periodicity of the 

 intermittent forms of malarial fever. 



The President said they had heard nothing more on the subject at present 

 than what Dr. Manson said in his communication. 



Dr. Mackenzie said that in a form of relapsing fever they had a period of 

 pyrexia, succeeded by a period of apyrexia. In the pyrexial period the 

 Spirilla were always found. This fever could be communicated by inocula- 

 tion, but it was only communicable in that way at a time when the Spirilla 

 were present in the blood. 



Mr. Michael said that he believed the question as to the mosquitos was 

 looked into at the time it arose, and he believed that just as in this country 



JouRN. Q. M. C, No. 43. h 



