I20 



PROTOZOA 



fever recently recognised on the West Coast has been found to bo 

 the early stage of the sleeping-sickness, thai; well-known and most 

 deadly epidemic of Tropical Africa. Through the researches of 

 Castellani, Nabarro, and especially Colonel and Mrs. Bruce, we know 

 now that the parasite T. gamhiense is transferred l)y an inter- 

 mediate host, a kind of Tsetse Fly {GlossinaiMlpalis). ►Schaudinn's 

 full study of a parasite of the blood corpuscles of the Owl has 

 shown that while in its intracorpuscular state it resembles 

 closely the malarial parasites in behaviour, and in its schizogenic 

 multiplication, so that it was considered an Acystosporidian, 



under the name of 

 HaUcrLdium,\\j is really 

 a Tryimnosoma ; ^ for 

 the accomplishment of 

 successful sexual re- 

 production it retpnrei; 

 transference to the 

 gut of a gnat {Culex). 

 The germs may infect 

 the ovary, and give 

 the offspring of the 

 insect tlie innate 

 power of infecting 

 Owls. Thus a new 

 T. or. ^, , , .. ^ ^ c • light is shed on the 



Fig. 39. — Morphology ot Trypanosoma, a-f, Stages \n °_ ^ 



development of TnjiMnosoma nociuae from the Origin ot the Cocci- 

 active zygote ("ookinete"); h, first division of .];„pppp whnsp "bbmf s " 

 nucleus into larger (trophic) and smaller (kineto-) '-ii^^^flt!^ ^^^ ii'J^t; uidbUfc, 

 nucleus ; c, d, division of smaller nucleus and its in the insect llOSt re- 

 transformations to form " blepharoplast " and myo- -, ■, rr 

 nen.es ;/, adult Trypanosoma ; g! h, i, Treponema Semblc Trypanosoma 

 zeemannii of Owl ; rj, Trypanosonie form ; h, in their morpholooy. 

 Suirochaeta form ; i, rosette aggregate. (After ^1 -, rn- i 



Schaudinn.) The humaii Tick 



fever of the Western 

 United States and the epizootic Texas fever are known to be duo 

 to blood parasites of the genus Firoplasma (Bahesia), of which 

 the free state is that of a Trypanosoma It appears certain that 

 Texas fever, tliough due to Tick bites, is not transferred directly 

 from one beast to another by the same Tick : but the offspring 

 of a female Tick that has sucked an infected ox contains 

 Trypanosonie germs, and will by their bites infect otlier animals. 



' Doubts still subsist as to the interpretation of Sehaudinu's observations. 



