28 



WATER AND SOLID CONSTITUENTS OF BLOOD AND SERUM. 



with the number which exists in the blood of the Vertebrata. In this class, we 

 find only colorless corpuscles. 



In the Braiicliiostoma or Ampldoxus, the connecting link between the highest 

 orders, the MoUusca and Fishes, the blood, like that of the Invertebrata, is described 

 as containing only colorless corpuscles, and exceedingly rich in water, and corre- 

 spondingly poor in solid constituents. 



As the organs and apparatus are developed, ilie Mood is correspondinghj improved-. 



The increased developjment of the cerebrospinal system, and the organs of vertebrate 

 animals, is attended by a corresponding increase in the solitary gland-cells of the blood. 



In this class, the number of blood-corpuscles is, as a general rule, least in cold- 

 blooded animals, and greatest in Birds and Mammals. There are, however, excep- 

 tions to this rule. I have found the number of blood-corpuscles in some cold- 

 blooded animals, especially Serpents, higher than that of some Birds and Mammals. 



The following table will illustrate this fact: — 



Name of obscrYcr. 



Name of animal. 



Blond-corpuscles in 

 1000 parts of blood. 



Jos. Jones .... 



liana cateshceana (Bullfrog) ..... 



45{).12 





Emys terrapin (Salt-water Terrai)in) 



44t.28 



If 



AUiyator JlJississippiensis (Alligator) 



364.08 



u 



Iletcrodon p/afi/r/iiitos (hlog-wose Yi\)Gv) 

 Psaimnopliis Jiagelliformis (Coacbwliip Snake) 



444.84 





488.80 



" .... 



Cohther constrictor (Black Snake) 



469.20 



( ( 



Ardea nycticorax (Heron) ..... 



315.84 



< I 



Syrnium nehulosiim (Hooting Owl) 



421.36 



Andral, Gavarret, and Delafond 



Horse ......... 



326.20 



Dumas and Prevost 



Horse ......... 



368.00 





Goat ......... 



408.00 



Nasse ..... 



Goat - . 



344.00 



Jos. Jones .... 



Cnr-Dog ........ 



■363.64 



f 1 



Cur-Dog ........ 



322.16 



Dumas and Prevost 



Dog 



495.20 



II II 



Calf 



364.80 



Notwithstanding the differences in the number of blood-corpuscles, the differences 

 of temperature were preserved, not only between the warm and cold-blooded 

 animals, but also between the individual species of each class. 



The thermometer indicated a temperature of over 100° in the Heron, having 

 only 364.08 parts of blood-corpuscles, whilst in the Frog, Serpents, and Chelonians, 

 having nearly double the number of blood-corpuscles in a given quantity of blood, 

 the thermometer indicated a temperature several degrees below that of the sur- 

 rounding medium. 



Several physiologists assert that the sole office of the blood-corpuscles is to carry 

 oxygen in, and convey carbonic acid gas out of the animal economy. If this be 

 true, the temperature of an animal would, at first sight, seem to be determined, in 

 great measure, by the number of its blood-corpuscles; but the temperature also 

 dej^ends upon the velocity of transfer of the oxygen, and consequently upon the 

 rapidity of the circulation. Many facts, however, might be brought forward, to 



