}825.] Scientific Notices — Zoology, 385 



1. I forced air into the vena cava ascendens, v/hich inflated 

 the right auricle and ventricle, and passed into the lungs through 

 the pulmonary artery into the splanchic aorta; also into the 

 systemic aorta through the valvular opening at its base ; the 

 blood into the superior cavse regurgitated. 



2. I fojrced air into one of the pulmonary veins which inflated 

 the left. auricle and ventricle, passed into the systemic aorta,, 

 and the subclavian trunks which leave the super cardiac sacs,' 

 (each of the large arteries are dilated immediately on leaving the 

 heart^i and are so united as to appear externally as a single 

 sac.) 



The circulation in the animals is briefly as follow : 1st, The 

 blood passes from the right auricle into the ventricle of the same 

 side, and in this cavity there are four openings, 1. One leading 

 from the auricle; 2. One into the pulmonary artery; 3. One,, 

 into the splanchic aorta, carrying black blood to the viscera^^ 

 and 4. One into the systemic aorta, by the valvular communi- 

 cation of the circulation when that through the lungs is impeded 

 by expiration. During expiration there is still some pulmonic 

 circulatioHj a small quantity of blood passing from the lungs 

 through the left auricle to the ventricle of the same side, from 

 whence it has a direct passage into the systemic aorta; the valve 

 at its base will not even permit air to pass into the right side of 

 the heart, nor will the semilunar valves of the aorta permit regur-? 

 gitation, so that the only mixture of black and red blood takea* 

 place in the systemic aorta during expiration or collapse of the 

 lungs. The systemic and splanchic aorta do not unite until 

 after the viscera have been supplied with blood by the latter. 

 In the land lizards there is no necessity for that complicated 

 structure which exist in the crocodiles, and the ventricles com- 

 municate freely with each, other. — (Harlan. Jour. Acad. N. S# 

 Phin '^^^"^oo \89fel nfiHo^i 5XU ^mtyiOiiOf^ 



(t^^ipm^ Float of Janthina. By Tteynell^Cp^t^g^M.D. ^ 



Sorrie have asserted that the animal of J6f?z/fea is capable of^ 

 absorbing the air of the vesicles and refiUing them at will, in ordepi 

 to sink or rise in the water, but Cuvier could not discover mijr^ 

 communication between the animal and the float, or any cavity? 

 within the animal which could contain the air when absorbed ; 

 he, therefore, was inclined to consider it as a rudimentary 

 operculum. 



During a voyage to the East Indies, I had several opportu^ 

 nities of observing the mode in which this organ is Qonstri;cte(| . 

 by the animal. \ j^, ,U. ,-. , Ah^^V^ikt 



Individuals being placed in a tumbler of brine, and a pprti^^jj 

 of the float t)eing removed by scissors, the animal very sopj^j, 

 commenced supplying the deficiency in the following manne?;; 

 the foot was advanced upon the remaining vesicles, until, about^ 



New Series, vol. x. 2 c 



