TRANSACTIONS OF SECTION D. 



^83 



;. Tlie raegali- 

 vpvtical parallti 

 * tlie lines of 

 erior shell alone 

 )00. 



radial iiiir mw^, 

 lie intt'nuediiit' 

 cliitou tho ews 



the touch ormii 

 liiuf-'ina, Loric;!, 

 113 thiM'o arc n 1 

 I margins tif tin 



b will prnbaWy 

 hitherto rrnvid 



ns of the t'liito- 

 The 1 e^'inentary 

 ■», entirely unre- 

 ) act as a secure 

 la wliich in the 

 present in otlitT 

 f these latter in 



3 te<^mentura in 

 t network, The 

 3, recoprnised th' 

 the shells of this 



vn to a nieraiiir 

 tuni of the sliells 

 !U, in which the 

 e descrihed and 



ustrated memoir 

 )f Microscopical 



apad the obsor- 



Hie Dodo. 



tinf^ specimen of 

 r to the Oxforl 

 • birds in beins: 

 ,11-kaown old oil 

 in each <n'0up of 

 from the siieatli 

 An illustrated 

 ■ty in the spring 



nnparabk with 

 ;S0N. 



13, On the BlatomacfiHs remains in fJh' Luke Deposits of Nova Scotia. 



Bij A, H, JiIackay. 



Subsection of Physiology. 



1, 0)t the Demonstration of an Apparat^is for Becordinri Changes of Volume. 

 Bij Professor K. A. Schafeu, F.Jl.S. 



2. Tiemarlcs on the J'rililem of Aqvatic Breathing. 

 Bij Professor McKkxhrick, M.B., F.li.S. 



:>, On the Biliary Concretions ; demovx'rating a Uniformifi/ iii the Consfritc- 

 fion of Concretions in the Animal, Vegetable, a)id Mineral Kingdoms. 

 By Dr. G. Haulky, F.li.S. 



4. On the Secretion of Oxalic Acid in the Dog. 

 By T. Wesley Mills, M.A., M.D. 



This paper describes the results of a diet of (1) Flesh, (2) Flesh and fat, and 

 (A\ of Flesh and carbohydratt-s, on the secretion of oxalic acid in the dog-. It 

 consists of (1) A comparative examination of the diflerent metliods in vogue for 

 the quantitative determination of oxalic acid in the urine of man, and .shows that 

 Scliultzen's method is the best ; (2) The perfecting of a metliod for the deternii- 

 natiou of oxalic ncid in dog's urine ; (o) An application of this method to the 

 proljlem proposed in the beading of this paper. 



A dog was kept under constant observation, punctually fed dail}% the urino 

 I'tiuuVL'd, its quantity, reaction, specific gravity, &c., determined, diluted to a 

 detinite volume, tiltered, and its nitrogen and oxalic acid determined. A 

 complete tabular statement of the results was given. The principal conclusions are 

 as follows : — 



(1.) Under all three diets given oxalic acid was daily found in the urine in 

 determinable quantity. 



(2,) The average for seven days' flesh diet was •Oil.'] gramme. It will be seen 

 tliat this was larger than by either of the other diets, and the strong acid reaction 

 cfthe urine throughout points to the flesb diet as a cause of the same, 



(3.) The average under diet (2) for five days, "0055 gramme, denotes a decided 

 failing oft" under the substitution of fat for flesh. 



(4.) The average under diet (3) for seven days is "OOSS gramme, and shows that 

 carbohydrates do not increase the secretion of oxalic acid, but the contrary. 



The animal was througiiout kept in nitrogenous equilibrium. 



apti. 



5, On the Mechanism of Absorption. By Professor E. A. Schafeu, F.li.S. 



It has hitherto been alnuxv universally held that the mechanism of absorption 

 of aUmentary substances from the intestinal tract is strictly analogous to the 

 passage of fluids through moist animal membranes, and it has been considered a 

 sulRcieut explanation of the process to assert this belief, and thus to account for 

 tlie passage of the comparatively diffusible peptones, sugars, salts, and water, into 

 the albuminous fluids which occupy the blood-vessels and lymphatics. 



But there are many objections to regarding absorption as a mere example of 

 pliysical osmosis. For the difference in the osmotic eqtiivalents of the digested 

 food materials and of the blood or lymph is comparatively small, and quite in- 

 sufficient to account for the rapidity with which absorption may occur, ftforeover, 



