730 DH. ". n- FAXTiiAM OX [May 3, 



Grouse wliicli would lu- cousidere.l perfectly healthy by keepers 

 have often contained a few Avox'nis. Tlie causjil factor of disease 

 in adult grouse is the larval stage of Trichostrongylm jyergracilis, 

 as shown by the researches of Dr. Leiper (Abstr. Proc. Zool. 8oc. 

 Lend. No. 80, March 1, 1910). The adult Trichostrongi/las occurs 

 in the ca*ca of grouse, and sets up inflaumiation therein. In the 

 blood of three adult birds dying on the moors from grouse disease, 

 I obtained dilierential leucocyte counts which may be thus sum- 

 marised : 



Eosinophiles 23-5 to 42-0 per cent. 



Polymorphonuclears 7"5 to 14-0 ,, ,, 



Mononuclears 6-0 to 10-0 „ „ 



Lymphocytes 44-0 to 62-5 „ „ 



Mast cells 0-5 per cent. 



Contrasting these counts with those given for normal grouse, 

 the occurrence of eosinophilia is deduced. All three of these 

 birds, dying of " grouse disease," had many Hymenolepis mia^02)S 

 in their^duodenum in addition to 7Vichost)-ong)/las in the cajca. 



Eosinophilia is often associated with helminthiasis in mammals. 

 Helminthiasis in grouse results not only in an increase in the 

 number of eosinophile leucocytes, but also in a diminution of the 

 number of erythrocvtes in the diseased birds. Thus the number 

 of red cells found^ in an adult cock grouse dying from hel- 

 minthiasis was 3,250,000 per cubic millimetre— the numl)erof red 

 cells for a normal cock grouse being about one million more. 

 The hi^moglobin value estimated by Tallqvisfs scale was 60 for 

 a grouse suffering from helminthiasis and 80-90 for healthy adult 



grouse. . . 



In spite of the incomplete c-haracter of this investigation of the 

 l)lood of the QTouse (due to the lack both of material and time at 

 my disposal),' I think that there are sufficient results contained 

 herein to emphasise the importance of parallel investigations of 

 the blood in connection with all animal diseases. 



References to Literature. 



Adami, J. G. (1907).— Inflammation, an Introduction to the 

 Study of Pathology. 240 i)p. London: Macmillan & Co. 



BuRNETT,'S. H. (1908).— The Clinical Pathology of the Blood of 

 Don'iesticated Animals. 15G i)p., 4 pis. Ithaca, N.Y., 

 LT.S.A. : Taylor & Carpenter. (Blood of Fowl, PI. 3.) 



CuLLEN, E. K. (1903). — "A Morphological Study of the Blood 

 of certain Fishes and Birds, with special reference to the 

 Leucocytes of Birds." Bull. Johns Hopkins Hosp. xiv. 

 pp. 352 356. 



l)AN"rsriiAivOFF, W. (1908).— "Untersuchungen iiber <lie Eut- 

 wickbing von Blut und Bindegewebe bei Vogeln.'" Ai-chiv 

 f. Mikroscop. Anatomic, 73. pp. 11 7-1 Ml. 2 ])ls. 



