HA RD WICKE'S SCIENCE- G OS SIP. 



13 



in China, Africa, the Mauritius, Bermuda, Brazil, 

 etc., all mosquito countries.* 



The organism described in this note is a filiform, 

 parasitic Nematoid, about i z in. in length, and j^jj in. 

 in transverse diameter ; it resembles the familiar 

 Anguilluke found in stagnant water, damp moss, 

 etc. It, however, differs from these in being en- 

 closed in a hyaline sheath, in which the worm can be 

 seen to elongate and contract itself. It is difficult to 

 make out the internal organization of the Filarise, the 

 alimentary canal is not distinctly traceable, and the 

 contents are mainly granular with a marked conden- 

 sation in parts. Dr. Lewis considered the jSTematoid 

 as he found it in man, to be an embryo, and his later 

 investigations brought the adult form to light. The 

 mouth-parts have puzzled me ; my sketches from two 

 worms, both obtained alive, indicate differences of 

 structure, or of position ; but the examination of 

 other specimens has not cleared this up. The 

 hyaline external sheath is often markedly apparent ; 

 and in dead and stained specimens, the body is 

 generally contracted in it at one or both ends : my 

 drawings illustrate this feature. The person from 

 whom I obtained my specimens suffers from general 

 debility and haemorrhoids, and occasionally from a 

 mild form of eczema ; but in all other respects he 

 can be said to be in fair general health. The mode 

 of obtaining the worm from the blood is simple 

 enough. The end of the finger is tied round with 

 twine or pack-thread, and when slightly congested is 

 lightly pricked' with a sharp sterilized dissecting 

 needle. The droplet of capillary blood thus secured 

 is taken up on one or more clean cover-glasses, and 

 pressed out as thin as possible on a cleaned slide. 

 A half-inch objective suffices as a finder ; but a 

 Zeiss D, or an Economic 1 in. is necessary for the 

 detailed examination of the worms. These were the 

 powers used by me ; though my drawings were made 

 under a student's \ in., and a Seibert's ^ in. w.i. In 

 all cases the .illustrations have been drawn with the 

 paper at a greater distance from the eye-glass than 

 the normal ten inches. This has been done merely 

 to get larger figures and details. The Filarise con- 

 tinue in active motion for many hours. As a stain 

 roseine will be found to answer the double purpose 

 of killing the worm, and also of staining it. In 

 blood from the same person I have twice, on separate 

 occasions, found what I took to be the moult of one 

 of the Sarcoptes. There was no itch present, and it 

 was denied that there was any previous history of the 

 complaint. Are these Sarcoptes to be regarded as 



* The Filarise come to the surface of the skin between five 

 and six o'clock in the evening, and seven or eight o'clock in 

 the morning, so that they are handy for mosquitoes during the 

 hours when those insects are most numerous. The worms 

 retreat into the tissues during the day. Though eyeless, they 

 seem to possess a ligktsense, and to avoid light. What effect 

 would the long Polar day have on these parasites, in which 

 periodicity is such a marked characteristic? Would it puzzle 

 them out of existence ? — W. J. S. 



pathogenic to the form of eczema which does occa- 

 sionally trouble the patient ? 



The prevalence of the latter disease at times in 

 Bengal, leads one to enquire if some skin complaints 

 distinguishable from itch, and termed eczema, may 

 not be contagious, and caused by a parasite ? 



Numerous red blood corpuscles in the case I have 

 in view are crenated, a few curious abnormal forms 

 being delineated in my drawings ; but for this feature 

 the Filariae may not be responsible. 



Dr. Lewis's investigations led to his examining 

 other animals, with the result that he obtained allied 

 Nematoids from the Indian pariah (or native street-) 

 dog, and the Indian crow. More than one-third of 

 the dogs he examined were thus affected, the 

 Nematode in them being smaller than in the case of 

 the human parasite ; while the blood of one half the 

 crows he examined also swarmed with Filarise, which 

 were about one-third the length and one-half the 

 width of the human parasite. In the Nematoids from 

 both the crow and the dog there were no indications 

 of an enveloping hyaline sheath ; and m the canine 

 worm the internal structure was in his opinion 

 slightly more advanced in respect to differentiation 

 etc., than in the human worm. Lewis also examined 

 mosquitoes, and was able to obtain a constant supply 

 of these insects in a filarious condition from a room 

 occupied by five servants, one of whom harboured 

 Filariae in his blood. This man had been in the 

 place for several years, and was not known to have 

 suffered from any special disease. I have myself 

 succeeded in finding filarious mosquitoes, but under 

 circumstances which, as in the case of Dr. Lewis's 

 servant, readily explained their presence. He 

 repeated the experiments of Dr. Manson of Amoy 

 (China), and discovered that fourteen per cent, of the 

 mosquitoes he caught at random had Filariae, which 

 he considered a proof that in Bengal filarious blood 

 cannot be very uncommon. As he points out, it is 

 necessary in examining mosquitoes for these Nematoids 

 to observe whether the blood in them is mammalian 

 or avian. The following details are based on Lewis's 

 papers, and may be useful. 



Embryo guinea- 

 worm . 



Trichina . . 



Sheath 



None 

 None 



Length. 



In. 



Habitat. 



Blood . . 



' Cellular 

 tissue 



Muscle . 



Form. 



(Head round, 

 t tail pointed. 



Ditto 



/Head pointed, 

 I tail blunt. 



A few sentences in conclusion with regard to the 

 milder forms of Filariosis (the term applied by 

 Lancereaux to the deceased condition caused by the 

 Filarise), may be interesting and appropriate. 

 Lancereaux, who has given a complete resume of the 

 whole subject, considers the parasite enters the 

 system by the alimentary canal, and he recommends 



