Tissue of the Tongue in Inflammation. 



395 



In experiment 6 (see fig. 4) the observations were continued successfully 

 for seven days, during the whole of which period the circulation was 

 vigorous, although active emigration took place. Neither in this nor in 

 any of the other cases was any extravasation of coloured blood-corpuscles, 

 either from veins or capillaries, distinctly viewed. In this respect there 

 may be a difference between the frog and toad. 



In experiment 8 no exudation took place during the first day, the circu- 

 lation going on apparently normally. Subsequently leucocytes began to 

 escape, and exhibited their usual character and behaviour. The observa- 

 tion was continued for three days, but no change occurred in the fixed 

 corpuscles. 



In experiment 11 the observation was as successful as in experiment 

 6. The circulation was vigorous until the sixth day ; emigration was 

 abundant, and commenced immediately after the commencement of the 

 observation. In the course of the sixth day it became feeble, and it was 

 then observed that the connective-tissue corpuscles, although retaining 

 their form, lost their transparency and became granular. 



EXPLAI^ATION OF PLATE 8. 



Fig. 2, Diagram of vertical section of tongue, distended. A, papillated surface ; B, sub- 

 mucous muscular layer ; C, smooth under surface of mucous membrane, 

 forming wall of the larger lymph-sac, D ; G-, principal venous trunks ; H, 

 principal arterial trunks, which are accompanied by nerves not shown ; F, F 

 muscular bundles ; E, fine transparent membrane of connective tissue lining 

 the lymph -sacs, and forming a continuous sheath to the bundles of muscular 

 fibre. In this membrane are the fixed corpuscles, the subjects of observation. 



Fig 3. Field of view in Experiment 5 at the commencement of the observation. 



Emigration has not commenced, but in the vein A the leucocytes (P, F) begin to 

 tend towards the internal surface of the wall. Through the capillary B a few 

 coloured corpuscles are passing. C, C are the fixed corpuscles of the tissue. 

 The fine lines are single fibres of connective-tissue. E, E are the red blood- 

 corpuscles. 



In this experiment, in which, as already stated, the observations were con- 

 tinued for five days (from Oct. 23 to Oct. 29), I was able to bring the same 

 field into view from time to time during the whole period. The vein marked 

 D was at the beginning of the observation obliterated, having been injured in 

 preparation. Towards the third day blood began to pass through it, and 

 soon the circulation through it was completely reestablished. In this case the 

 connective-tissue corpuscles represented (COCO) were watched with the most 

 minute attention. Notwithstanding that the emigration was most abundant, 

 so that before each observation it was necessary to cleanse the surface of the 

 lymph-sac by irrigation, as above described, there was no alteration of form 

 whatever, either in the corpuscles themselves or in their nuclei, nor did they 

 exhibit the slightest tendency to divide. 

 Fig. 4 represents the appearances exhibited by a vein and the neighboviring textural 

 elements, at a later stage. In the vein Y, notwithstanding that the circulation is 

 still vigorous, an abundant emigration is in progress. Some colourless cor- 

 puscles adhere to the walls, others have already escaped and are crossing tlie 

 field, mostly clinging to the bundles of connective tissue, and exhibit various 



