EFFECTS OF THIRST, ETC., ON EMTS SERRATA. 81 



CHAPTER IV. 



EFFECTS OF STARVATION AND THIRST, COMBINED WITH A CHANGE 

 OF DIET, UPON THE FLUIDS AND SOLIDS OF CARNIVOROUS CHE- 

 LONIANS. 



Series I. — Experiments upon the Yellow-Bellied Terrapin {Emys serrata). 



39. Examination of a female Emys serrata which was starved four weeks, and 

 then transferred to a tub of water, and abundantly supplied with Purslain (Portu- 

 lacca oleracea). 



It remained in the tub of water for forty-two days. 



Weight, May 25 ...... 23.696 grains. 



June 21 ..... . 19.472 " 



Loss of weight in twenty-seven days — during which period it 



was deprived of all food and drink .... 4.224 " 



Weight, August 2, after remaining forty-two days in the tub of water 25.333 " 



Increase of weight in the forty-two days . . . 5.861 " 



Gain above the original weight of May 25, . . . 1.637 " 



The color of the blood was intermediate between arterial and venous. 



The serum was of a light yellow color, resembling that of the Gopher (Tesiudo 

 polyphemus) which subsists entirely upon vegetable food. The serum of the Emys 

 serrata supplied with animal food, is always of a bright orange color. Here we 

 see that the color had been changed from orange to light yellow by a change of 

 diet. 



In one portion of blood which was set aside, the fibrin did not coagulate until 

 nearly all the blood-corpuscles had settled to the bottom, thus affording a trans- 

 parent clot. 



The portions of blood drawn last, coagulated much more rapidly than those 

 drawn first. 



The cellular tissue in all parts of the body of this Terrapin, was permeated by 

 a limpid albuminous fluid, which coagulated when removed from the body. The 

 coats of the peritoneum, the cavity of the abdomen and the pleura, contained large 

 quantities of this fluid. The amount of this serous fluid, collected without any 

 special care, was more than five fluidounces, equal to 2420 grains. Its specific gravity, 

 1005.9. As the blood flowed from the wound in the neck, this serous fluid passed 

 into the bloodvessels, to supply the loss. This was shown by the change in the 

 specific gravity of the serum. That obtained from the portions of blood first 

 11 



