130 



Further Observations on Micro-Filari^, with Descrip- 

 tions OF New Species. 



By Patrick Manson, M.D., Amoy. 



Communicated {with a Prefatory Note) by the President. 



{Read June 26th, 1880.) 



PLATES VIII, IX, X. 



The interesting letters which I have now the honor to submit 

 to the Club must be regarded as a continuation of Dr. Hansen's 

 former communication. Not merely does Manson refer to an 

 abundant confirmation of his discovery respecting the periodical 

 emigration and immigration of the human larval filariae, but he 

 here supplies us with a new fact, pointing apparently to the 

 lymphatic system as the probable home or head-quarters, so to say, 

 of the sexually mature worm (Filaria Bancrofti). For myself, 

 this ** find " has especial interest, inasmuch as it was the circum- 

 stance of my detection of the chorional envelope of an ovum in 

 blood sent from Australia and my communication of the fact to Dr. 

 Bancroft that led to the original discovery of the sexually mature 

 worm. This has been acknowledged by Bancroft. Curiously 

 enough, in a letter received only a few days back, Dr. Sonsino (who 

 has largely contributed to our knowledge of the filarial, as they 

 occur in Egypt), requested my opinion as to the precise residence or 

 " ordinary abode " of the sexually mature Filaria. I think Hanson's 

 find tends to confirm the view that I have already entertained, if not 

 decidedly expressed, that the home of the adult worm is to be found 

 in the lymphatic channels. I own that the circumstance of my 

 original " find " is somewhat puzzling, but the presence of the 

 ovum in blood sent to me from Australia may have been accidental. 

 Dr. Bancroft's detection of the adult worm in an enlarged gland 

 or " lymphatic abscess " and Dr. Hanson's present " find " point to 

 the conclusion just advanced. Not only as regards size, but also 

 as regards contour, do the empty ova detected by Manson and 



