530 



Zoological Society. 



6000 

 5333 



4500 



10666 

 4000 



5918 



Blood from a prick of the ear. 



The preceding measurements 

 confirm my former observations, 

 published in the Proceedings of 

 the Zoological Society, Aug. 9, 

 1842, p. 107,— that the blood- 

 discs of the Ibex are slightly 

 smaller than those of the Goat. 



The Kid between these animals 

 appears to have generally larger 

 and more variously-sized blood- 

 discs than either of the parents. 



The observations were favour- 

 ably made for comparison, because 

 the blood of the three animals 

 was taken and examined from the 

 same part, on the same day and 

 hour, and under the same circum- 

 stances. 



RODENTIA. 



Hackee Squirrel (Sciurus Listeri, 

 Ray). 

 4000 

 3800 



5333 

 3200 



3948 

 Blood from a vein of the ear. 



Quebec Marmot {Arctomys Em- 



petra, Schreb.). 



3600 



3330 



4570 

 2900 



3503 



Blood from a prick of the lip. 



Harvest Mouse (Mus messorius, 



Shaw). 



4000 



4570 



6400 

 3200 



4268 



Thus this little animal, the 

 smallest of the British Mammalia, 

 has blood-corpuscles larger than 

 those of the horse, as may be seen 

 by comparing the measurements 

 now given with those of the blood- 

 corpuscles of the horse, published 

 in my Appendix to Gerber's Ana- 

 tomy, p. 43 ; and a reference to 

 the dimensions of the blood-cor- 

 puscles of numerous Rodentia de- 

 tailed in the same work, p. 47-50, 

 will show that the corpuscles of 

 the Harvest Mouse are rather 

 smaller than those of any animal 

 yet examined of this order. 



The blood of the Harvest Mouse 

 was obtained from the heart, in 

 one case about twelve, and in 

 another twenty-six hours after 

 death, in cool weather. 



For opportunities of examining 

 these animals, I am indebted to 

 the kindness of Mr. Griffith and 

 Mr. Prince. 



Canada Porcupine (Erethizon 



dorsatum, F. Cuv.). 



3555 



3428 



3200 



4572 

 2666 



3380 

 Blood from a prick of the skin 

 of the nose. 



Beaver (Castor Fiber, Linn.). 

 3555 

 3303 

 3200 

 3000 



5000 



