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V. — The Structure of the Coloured Blood-corpuscles of Amphiuma 
tridactylum, the Frog, and Man. By Dr. H. D. Schmidt, 
Pathologist of the Charity Hospital, New Orleans, La. 
{Tahen as read before the Royal Microscopical Society, April 3, 1878.) 
Plate IV. 
Notwithstanding the numerous investigations which have been 
made for the purpose of determining the true structure of the coloured 
blood-corpuscles, the views on this important subject, it appears, are 
still varying, leaving it an object for further research and dis- 
cussion. 
Formerly, these bodies were almost universally regarded as true 
cells, consisting of a cell-membrane, enclosing the protoplasm ; and 
this view was entertained of the round bi-concave non-nucleated 
blood-disks of the blood of the Mammalia, as well as of those ellip- 
soidal nucleated bodies met with in the blood of other classes of 
vertebrated animals. 
EXPLANATION OF PLATE IV. 
In order to enable the reader to compare the relative sizes of the blood- 
corpuscles discussed in the paper, all figures, with the exception of 45, 46, and 
47, have been represented enlarged by the same magnifying power, viz. 420 
diameters. 
Fig. 1. — Front view of a coloured blood-corpuscle of Amphiuma tridactyliim. 
Fig. 2. — Side view of the same. 
Figs. 3 to 12. — Various forms of coloured blood-corpuscles of the Amphiuma, 
produced by spontaneous contraction of the protoplasm. 
Fig. 13. — Representation of a coloured blood-corpuscle of the Amphiuma, the 
membraneous layer of which has burst; a, colourless protoplasm exposed to 
view ; 6, membraneous layer (coloured). 
Fig. 14. — Fragment of a coloured blood-corpuscle found in the fresh blood of 
the Amphiuma. 
Fig. 15. — Coloured blood-corpuscle of the Amphiuma, enclosing minute 
crystals. 
Fig. 16. — Another, enclosing vacuoles. 
Fig. 17. — Another form of vacuoles. 
Figs. 18, 19, and 20. — Coloured blood-corpuscles of the Amphiuma, treated 
with water. 
Figs. 21 and 22. — The same, with their nuclei escaping through a rent in the 
membraneous layer. 
Fig. 23. — Nuclei, escaped from the corpuscles, with their contents escaping 
through a small rent in tlieir enveloping membrane ; a, the contents escaping in 
the form of a small sphere ; 6, the same, after having been treated with a weak 
solution of chromic acid ; c, the contents escaping in the form of a cone. 
Fig. 24. — Singular appearance of a coloured blood-corpuscle, treated with 
water, and subsequently with a weak solution of chromic acid. 
Fig. 25. — Coloured blood-corpuscle of Amphiuma, treated with chloroform 
vapour. 
Fig. 26. — Coloured blood-corpuscle of Amphiuma, treated with chloroform 
liquid. 
Fig. 27. — Coloured blood-corpuscle of Amphiuma, treated with diluted acetic 
acid. 
VOL. I. 
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