VETERINARY MEDICINE. 285 



A coiisukTMblo varialioii was found in tlio variability of tlu! virus. Finding; 

 tliat one particular kind of virus did not conipletoly protect aj^ainst subsequent 

 inoculation of (lie S(>cond or tliird virus, u polyvalent virus was made composed 

 of blood collected from mules showing relapses in practice, the ordinary virus, 

 the Tzaneeu virus, the lUilawayo virus, and blood collected from spontaneous 

 cases of the disease. These were mixed together and injected into a horse 

 which developed the disease. The animal was tapped during reaction and the 

 virus obtained was the polyvalent virus. 



While this virus did not completely prohibit a reaction from its constituents 

 it prevented mortality. The author states that experience in practice has 

 shown that an inoculation of mules with any of the virus used protected 

 against death to the extent of 0S.7 per cent. P.realvdowns vary in the different 

 districts and even in the same locality. In the laboratory it was possible, with 

 blood obtained from immunized animals that died from horse sickness after 

 exposure, to break the immunity given by almost any virus. 



A malignant form, of canine distemper, M. White {Amcr. Vet. Rev., 3} 

 (1909), No. 5, p. 635). — The author has observed a canine distemper in Denver, 

 Colo., that is quite different from the usual form. The affected dogs are said 

 to show digestive complications, to bleed from the nose, and to discharge pus 

 with the blood. I^ater the mucus membrane of the mouth shows a brick-red 

 discoloration and inflammation, followed by bleeding from the month and 

 bowel. Death takes place within 7 days. It is estimated that from 5 to 10 

 per cent of the cases are of this severe form. 



Blackhead disease of turkeys, L. J. Cole (Rhode Island Sta. Rpt. 1908, pp. 

 207-290). — A brief account is given of the investigations now being carried on. 

 As noted below, this disease has been found to be due to organisms belonging 

 to the genus Coccidium. The investigations under way consist of a study of 

 the life history of the causative agent, its resistance to injurious substances 

 and conditions, its occurrence in and effect on other birds and mammals, the 

 means by which it might in nature be transmitted from one bird to another, etc. 



Blackhead, a coccidial disease of tui-keys, I.. J. Cole and P. B. Hadley 

 (Science, n. scr., 27 (lOOS), No. 70.'i. p. OO'i). — The authors believe they have 

 demonstrated that this disease is caused by a Coccidium which, according to the 

 nomenclature adopted, may be of the variety Coccidium cuniculi, and that 

 Amoeba mcleagridis Smith is probably the schizont stage in the development of 

 the Coccidium. The stages of the Coccidium most commonly found were the 

 schizonts and the macrogametes or oocytes. 



By means of feeding portions of cecal content or parts of ceca of diseased 

 birds, the disease was produced experimentally in turkeys, chicks, and sparrows, 

 but not in guinea pigs, kittens, or rabbits. In young turkeys the disease is 

 almost always fatal ; older birds may recover. It is doubtful if death is caused 

 directly by the Coccidium in the majority of cases; whether there is a specific 

 accompanying organism pathogenic to turkeys under these conditions, and less 

 so to chickens, has not yet been determined. In cases of perforation of the 

 cecum, death soon follows from acute p(>ritonitis. 



No method of treatment is at present recognized. 



A new parasitic disease of pigeons, A. Lanfkanchi (Mod. Zooiatro, 190S, 

 No. (J, »S'Hy>., pp. 2S0-,il7; <ihs. in Tierarzt, .'/7 (lOOS), No. 7, pp. l-lG-loO ; Vet. 

 Rev., 21 (1900), No. 107(), pp. G'/O, 550). — The author describes a new infectious 

 disease of pigeons in which death r(>snlts in from 10 to 20 days. Flagellates 

 were 'found in the saliva and salivary glands, bone marrow, blood, and peri- 

 toneal exudate, in small nodules forme<l in the internal organs, and in the feces. 



The young stages are said to be similar to those of trypanosomes. The i)ara- 

 site remains active for a long time in saliva and feces outside the animal body. 



