BLOOD. 



[ 101 ] 



BLOOD. 



thin, the surfaces of the corpuscles are rather 

 concave than convex, the nucleus projecting 

 somewhat laterally. 



The red corpuscles of the Mammalia are 

 not furnished with a nucleus, whilst in 

 Birds, Fishes, and Keptiles a distinct nu- 

 cleus exists ; this is usually oval, but some- 

 times rounded in the latter. 



The colourless corpuscles of the Vertebrata 

 (figs. 21-30 b), or the lymph-corpuscles, or 

 the blood-leucocytes as they are sometimes 

 called, are spherical, of a granular appear- 

 ance, highly refractive, and specifically 

 lighter than the coloured corpuscles. They 

 consist of a cell-wall containing numerous 

 larger or smaller granules and molecules, 

 with one or more nuclei. Acetic acid dis- 

 solves the granules, and brings the nuclei to 

 view. The cell- wall is often undistinguish- 

 able, unless water be added to the corpuscles, 

 which being imbibed, separates it from the 

 contents. When blood is kept at a mode- 

 rate heat, these corpuscles exhibit various 

 Amoeba-like processes, crawl over the slide, 

 and even take up particles of foreign sub- 

 stances, as vermilion, carmine, &c. 



The blood of the Invertebrata has not 

 been so thoroughly examined. In many of 

 them there are two circulating liquids one 

 coloured, and sometimes containing hsema- 

 tine, but no corpuscles ; the other colourless, 

 and containing rounded or irregular granular 

 colourless nucleated corpuscles (figs. 31-35), 

 much resembling the colourless corpuscles 

 of the Vertebrata, but remarkably prone to 

 shoot out processes like the Amoebae. 



The sizes of the coloured corpuscles of 

 many vertebrate animals are given in the 

 subjoined list, nearly all the measurements 

 being those of Gulliver. It may be re- 

 marked that, whilst the largest coloured 

 corpuscles occur in the Reptiles, the small- 

 est are found in the Mammalia, and that 

 the size of the corpuscles is in general 

 proportional to the size of the animal, in 

 animals of the same order, but not in those 

 of different orders. Thus, in the larger 

 Ruminants and Rodents the corpuscles are 

 larger than in the smaller ones, whilst the 

 smallest British mammal, the Harvest- 

 mouse, has corpuscles as large as those of 

 the Horse ; and in the common mouse they 

 are larger than in the Horse or Ox. 



MAMMALIA. 



Bimana. Man, 1-3200 to 1-3500". 

 Quadrumana. Chimpanzee (Simia Tro- 

 glodytes}, 1-3412; Monkey (Cercopithecus 



mono), 1-3468 ; Monkey, mean of eight 

 other species, 1-3450 ; Lemur, mean of four 

 species, 1-4077. 



Cheiroptera. Bat (Vespertilio murinus), 

 1-4175 ; Bat ( Vespertilio pipistrellus), 1-4324. 



Insectivora. Hedgehog (Erinaceus euro- 

 pceus), 1-4085; Mole ( Talpa europcea), 1-4747. 



Carnivora. Badger (Meles vulgaris), 

 1-3940; Bear, mean of five species, 1-3708; 

 Dog (Canis familiaris), 1-3542 ; Fox (Canis 

 Vulpes), 1-4117; Lion (Felis Leo\ 1-4322; 

 Seal (Phoca vitulina}, 1-3281. 



Cetacea. Dolphin (Delphinus Phocand), 

 1-3829; Whale (Balana Mysticetus), 1-4000 ; 

 Whale (Batena Boops), 1-3099 ; Manatee 

 (Manatus), 1-2400. 



Pachydermata. Elephant (Elephas inrfi- 

 cus), 1-2745 ; Horse (Equus caballus), 1-4706 ; 

 Pig (Sus Scrofa), 1-4230 ; Rhinoceros indi- 

 cus, 1-3765. 



Ruminantia. Camel ( Camelus bactrianus), 

 length 1-3123; breadth 1-5876; Dromedary 

 (Camelus dromedarius), 1. 1-3254, b. 1-5921 ; 

 Goat (Capra hircus), 1-6366; Musk (Mos- 

 chus javanicus), 1-12325 ; Stag (Cervus ela- 

 phus), 1-4324; Ox (Bos Taurus), 1-4267: 

 Sheep (Ovis Aries), 1-5300. 



Edentata. Armadillo (Dasypus sex-cinc- 

 tus}, 1-3457 ; Sloth (Unau, Bradywus didac- 

 tylus\ 1-2865. 



Rodentia. Guineapig (Cavia cobaya\ 

 1-3538; Mouse (Mus musculus), 1-3814; 

 Rabbit (Lepus cuniculus), 1-3607 ; Rat (Mus 

 Rattus), 1-3754. 



Marsupialia. Kangaroo (Macropus), mean 

 of three species, 1-3460. 



Monotremata. Platypus, duck-billed (Or- 

 nithorhynchus paradoxus), 1-3000. 



Birds. Chaffinch (Fringilla ccelebs), length 

 1-2253, breadth 1-4133; Cuckoo (Cuculus 

 canorus), 1.1-2028, b. 1-3600: Ezgle(Aquila), 

 mean of four species, 1. 1-1640, b. 1-3651 ; 

 ~Fow\(Gallus domesticus), 1.1-2102, b.1-3466; 

 Gull(Mew-,Zrwscemws), 1. l-1973,b.l-3839; 

 Humming-bird (Trochilus), 1. 1-2666; b. 

 1-4000; Ostrich (Struthio camelus\ 1. 

 1-1649, b. 1-3000 ; Owl (Strix flammed). 1. 

 1-1882, b. 1-3740 ; Parrot (Psittacus), mean 

 of twelve species, 1. 1-2042, b. 1-3724 ; Pi- 

 geon (Columba), mean of sixteen species, 

 1. 1-2135, b. 1-3679; Sparrow (Fringilla do- 

 mestica), 1. 1-2140, b. 1-3500. 



Amphibia and Reptiles. Crocodile (Croco- 

 dilus acutus), 1. 1-1231, b. 1-2286; Frog 

 (Rana temporaria), 1. 1-1108, b. 1-1821; 

 Lizard (Lacerta vivipara), 1. 1-1660 ; Siren 

 lacertina, 1. 1-435, b. 1-800 ; Toad (Bufo 

 vulgaris), 1. 1-1043, b, 1-2000; Triton (Lis- 



