su 



The Microscope. 



5 1 



6 ■■ 



Figures of the red blood-corpuscles of adult and larval lamprey eels, showing the appear- 

 ance in diflfer«^nt positions and the relative size in the different animals. Magnified 1 000 

 diam»ters Outlined with Abbe's camera lucida. Drawn by Mrs. Gage. From the 

 New York Medical Journal. 



A. Red bloO' I -corpuscles of the sea lamprey (Petromyzon marinus). a, face view of a 

 corpuscle; 6, optical section of a corpuscle on edge; c, face view of a corpuscle, showing 

 the nucleus after the action of one per cent, acetic acid; d cup shaped corpuscle. 



B. Red blood-corpuscles of the brook lamprey { Ammoccetes branchialisj . a, b, c, the 

 same as in A . 



C. Red blood-corpuscles of a larval lamprey 142 mm. long, a, 6, c, as in A. 



D. Red bloo4-corpuscles of a larval or embryo lamprey 9 mm. long, a, b, c, the same 

 as in A. 



E. Rouleaux of the corpuscles of the brook lamprey in optical section. In the lower 

 corpuscle a nucleus is indicated to .show that it is small and in the thickest part of the 

 corpuscle. It is visible only after the haemoglobin is partly or wholly removed from the 

 corpuscle. In the embryo, where the corpuscles are so small, the nucleus is faintly visible 

 in many corpuscles before the removal of the haemoglobin. 



F. Rouleaux of the 143 mm. larva focused on the upper surface. In both E and F the 

 corpuscles are shown of different sizes. Compare the maximum and minimum diameters 

 in the table of measurements. 



ANNOTATED BIBLIOGRAPHY. 



1. Gage, Simon H. — The Red Blood-Corpuscles of Lamprey- 

 Eels in Relation to Jurisprudence. New York Medical Journal, 

 Vol. XLYIII (1888), pp. 149-150. The main facts of the present 

 paper were given. 



2. Gegenbauer, C. — The Elements of Comparative Anatomy. 

 London, 1878. "In fishes, amphibia, reptiles and birds, they [the 

 red blood-corpuscles] are oval and bi-convex, for the center of each 

 surface protrudes slightly." p. 576. 



3. Gulliver, G. — The Works of William Hewson. London, 

 1846. Note CIX (p. 228), non-formation of rouleaux by the red 

 corpuscles of the camels. Note CXVII: "In the cyclostomes the 

 corpuscles are of the same figure as those of man's, and only 



