244 TRANSACTIONS OP THE CANADrA>f INSTIIUTE. [VoL. II. 



found in the blood finally all the intermediate stages between the fusi- 

 form and the red cells. 



Bizzozero and Torre* reject this view of the haematoblastic nature of 

 the red cells and state that though they are like red cells in some respects 

 they are smaller and unpigmented, while young blood cells are round in 

 form and always contain haemoglobin. These elements are also unlike 

 the leucocytes in their simple oval nucleus and non-contractile proto- 

 plasm. These authors believe that the corpuscles in question are related, 

 in spite of many points of dissimilarity, to the structures in mammalian 

 blood known as platelets. 



Hlavaf considers the fusiform corpuscle to be a variety of the white 

 cell brought about by the contractile capacity of the latter. 



Lowit| describes the transformation of the spindles into spherical forms 

 like that of the white cells with which he classes these elements. He 

 maintains that all forms of white blood cells may appear in the spindle 

 form, but he admits that certain stages of the developing red cell exist 

 in this form from which haemoglobin is absent. According to his view 

 the fusiform cell is not a separate species of white blood cell but only a 

 form of the latter which may appear under those conditions offered by 

 the circulating blood, and it may in some cases have a haematoblastic 

 nature. 



Eberth§ describes the elements as being spindle, club, or almond- 

 shaped, somewhat smaller than the red discs, probably slightly flattened, 

 possessing a finely granulated nucleus and an almost homogeneous cell 

 protoplasm which is chiefly gathered at the poles. Their contour does 

 not change, they have no amoeboid processes, and when they are 

 collected into great masses they never present a trace even of a yellow 

 or haemoglobin tint. When they are kept for hours in their normal 

 physiological condition, e. g., inside the bloodvessels of an excised piece 

 of mesentery, protected from evaporation, they have never been observed 

 to change in shape, they exhibit no amoeboid movement whatever and 

 they do not fuse together. In the spindles fixed by osmic acid there is 



*Virchow's Arch., Bd. 90. 



+Die Beziehung der Blutplattchen Bizzozero's zur Blutgerinnung und Thrombose. Arch, fiir 

 Experim. Pathologic, Bd. XVII., 1883. 



+Ueber Neubildmig and Zerfall weisser Blutkorperchen. Sitzungsber. der Wiener Akad., 

 Bd. XCII., Abth. III., 1885. 



Also: Ueber den dritten Formbestandtheil des Blutes. "Lotos," Jahrbuch fur Natur- 

 wissenschaft. Prag, 1885. 



§ Zur Kentniss der Blutkorperchen bei den niedern Wirbelthieren. Festschrift fiir Kolliker 

 Leipzig, 1887, p. 37. 



