110 



A H.KMOOREOAniNE OF MAMMALS 



Dillerences 



from 



//. gfrhlli 



(Christophers) 



//. iifr/illll in tho louse ( nfniintopi>ni.i Strphrnxi), iind wliirli I have seen in tlie (lea in the 

 case of //. Iliilfiiiiri. 



As the ji'i'lida is niictiirnal I tliou^lit it \\i\\ to c hlniiirciiiii mie iliiring the niglit, 

 anil at unee examine its hhxiil and oi'i^'ans. 1 [ailiil to liii>l thi' virniienle fni'in. m- 

 anvtliinfj; l)nt tlie free and eiidoj^hiliular tni])li()Zoites. 



It slionid lie said that to the lial<( il i Ve there is nil linill'id aji|iea|-anie pl-esentid hv 

 anv iif the viseera. 'I'lir spleen Seems never to lie enlarged, and, as far as ean he told, 

 the liver does not apiiear almornial. Neither do the uninvaded hejiatie eells present any 

 pathidogieal eonditioTi heyond a slijj;ht degree ul elondy swelling. 'I"he vessels and 

 capillaries are usnally full of Idood. 



Fnrtlier, it iniiy he stated that nunierons free forms (tropliozoites or nierozoites) 

 (Plate XI., Fig. <•) are, as a rnle, present in smears made from the liver, kidney anil 

 hone-marrow, and to a less extent in those from the spleen. Once in the hone- 

 marrow 1 notiiid parasites which had lucii liikiTi ii]i hy the large iiiononuelear 

 leucocytes. (I'late XL, Fig. <). Several gerliils have heen inoi-ulatid from infeited 

 jerhoas hut al\va\s with negative resnlts. 



Professor liaveran writes nie to say tliat lie lias now found the same parasite in 

 jerboas (./. orictit<i/in) from Tunis, so that, no donht, nimh information will soon he 

 fortliconiing regarding this interesting parasite of niamnnils. Tluinks to the kindness of 

 Captain Patton, I.JI.S., I have received one of Lient. ('hristojjhers' smear preparations of 

 the infecti'd hlood of the (u'rlii/hm IikHchs. His parasite closely resemhles that found 

 in jerhoas, hut i)resents some points of difference. Thus it exhihits idiromatin dots much 

 more frii|Uintlv and in more aliundaucr. l''urthir, forms sliowing a ta|icring md turned up 

 .so that tlir ]iarasite apjiroachcs a V shajie. are much moi'c in e\ iileuce. 



A Lkucocytozoon ok Mammals 



.*\ new 



leucocylojijon 

 A. OTwrii 



In May, 190"), while examining the hlood of a Norway rat {Mux <lirii»iiniiix). to nee 

 if the animal was the host of T. Lewisi or harhoured the luemogregarine I had found in 

 jerboas, I came across a parasite very similar in appearance to the latter, but situatid in the 

 extra-nuclear portion of the mononuclear leucocytes. The jiarasite, which is ovoid in 

 shape, has a well-marked nucleus separating two lightly staining portions. Its ends are 

 rounded and its dimensions in stained specimens hit ween it /i and lur) ^ in length hy 

 4'r) /I in hiiaijth. 



Although it is usually found in the light staining portion of the leucocyte I have come 

 across it lying hetween the lohes of a divided nucleus. (Plate XI., Fig. ./'). Thus it 

 appears to he of the nature of a karyolysus such as has heen descrihed in lizards. 1 have 

 examined the bloods of twelve Norway rats, six of tlnni being young animals, and 1 have 

 found the parasite in two instances. In the case of the first rat it was found in the hearts 

 hlood and in the spleen. In the latter, free forms were present in addition to those lying 

 in the leucocytes. The liver was congested, but neither in smears nor in sections were any 

 parasites visible. Section preparations revealed a condition of early chronic venous 

 congestion resulting in pressure atropln of hepatic cells whiih stained badly and had lost 

 their nuclei. 



No parasites were present in smears made from tin- kidney or bone-nnirrow. The 



