THE BLOOD AND THE LYMPH. 713 



lest (0-00094) in the Musk Deer ; seldom larger (0-005 of a line) as 

 in the Elephant. All the lower Vertebrata have, almost without 

 exception, oval, nucleated blood-corpuscles, of the shape' of a melon 

 seed. Those of Birds are from 0-004 to 0-008 of a line long, and con- 

 tain roundish nuclei ; those of the Amphibia measure between 0-008- 

 0-025 of a line in length, have round and oval nuclei, and are largest 

 in the naked Amphibia (Frog, 0-011-0-013 of a line long, 0-007-0-008 

 of a line broad ; Proteus, 0-025 of a line long, 0-016 of a line broad, 

 Salamander, 0-02 of a line long); those of Fishes, lastly, are mostly 

 0-005-0-007 of a line long, except that in the Plagiostomes they mea- 

 sure 0-01-0-015 of a line ; in the Lepidosiren they are 0-020 of a line 

 long, and 0-012 of a line broad. In Myxine and Petromyzon they are 

 0-005 of a line in diameter, round and slightly biconcave. In Amphi- 

 oxus the blood-corpuscles are absent.* The blood- Fig. 293. 



corpuscles of the Invertebrata resemble the colorless 

 cells of the blood in the higher animals, and are almost 

 always uncolored. 



The following should here be also noticed as extraor- 

 dinary constituents of the blood : 1, cells enclosing 

 blood-corpuscles, noticed by Ecker and myself in the 

 blood of the spleen and hepatic vessels, and elsewhere also in the blood 

 (vid. Mikroskop. Anat., II. 3, p. 369, et seq.) 2, pigmented and color- 

 less granule-cells, observed by myself, Ecker, Meek el, Virchow, and 

 Funke, particularly in cases of intermittent fever and diseases of the 

 spleen (1. c.) 3, pale, fine-granular, roundish aggregations, in the blood 

 of the splenic vein (Funke). 4, peculiar concentric bodies, three to 

 four times larger than the white blood-cells, similar to those of the 

 thymus (vid. Henle, "Zeitsch. f. rat. Pathol.," Bd. VII. p. 44), found 

 by Hassall in fibrinous clots in the heart. 5, cells resembling pus-cor- 

 puscles, in tumors of the spleen and leukaemia (Virchow) ; these bodies 

 are found in vast quantities, but, in their form, cannot in any way be 

 distinguished from the colorless blood-corpuscles. 6, caudate, pale or 

 pigmented cells (Virchow, "Arch.," II.) Besides these, should be no- 

 ticed, the morphological elements which are formed in the blood without 

 the body or in cases where the circulation has been obstructed the 

 fibrinous coagula and crystals. The former are seen in coagulated 

 blood, usually in the form of fine, extremely closely interwoven fibrils, 

 disposed irregularly ; occasionally as stronger, straiter fibres, having a 

 uniform width of 0-001-0-003 of a line ; not unfrequently also in the 

 shape of plates resembling epidermis scales (fibrinous flakes, Nasse). I 

 noticed crystals of a red color in normal blood in the year 1849 



FIG. 293. 1, blood cells of the Frog: a, viewed on the side ; b, on the edge ; r, rendered 

 colorless by water. 2, Blood-cells of the Pigeon : a, viewed on the side ; b, on the edge. 



* [Fid. Note, p. 707. TRS.] 



