242 TRANSACTIONS OF THE CANADIAN INSTITUTE. [VoL. 



II. THE FUSIFORM CORPUSCLES. 



The fusiform corpuscles, which measure 26,«x i6/^, are quite numerous 

 in the shed blood of NecUirus. They, as their name implies, are elong- 

 ated and oval, and with usually sharply truncated ends. They have no 

 cell membrane, and their protoplasm, especially at one or both of the 

 ends, is amoeboid or protrusible in the form of fine straight rays, which, 

 with careful observation, are sometimes seen to manifest a slow vibratory 

 motion. Sometimes these cells are fixed with the processes extended 

 (Fig. 22b). Often the protoplasmic periphery is formed of a series of 

 granules which render the exact outline indistinct. The protoplasm is 

 usually homogeneous, except for the presence of one or more vacuoles at 

 either end of the oval nucleus and a few granules which seem to be of 

 the same character as those of the periphery. 



The nucleus is oval usually and measures i6/>tx 14/^. It may in some 

 cases be lobed, and the lobation may have gone so far as to originate 

 several small spherical nuclei. It may be homogeneous or it may be 

 coarsely reticulated. Kept in a moist chamber the reticulated as well as 

 the homogeneous nuclei undergo a process of chromatolysis. In the case 

 of the reticulated nuclei the first stage of degeneration is seen in the tra- 

 beculae of the network becoming elongated and parallel, the elongation 

 occurring transversely to the long axis of the nucleus. At the same time 

 the spaces in the network become larger and the nucleus apparently 

 distended. This condition passes into that wherein the whole nuclear 

 substance becomes homogeneous or in which its chromatin forms a thick 

 zone next to the now spherical membrane. The history of the corpuscle 

 terminates with the disintegration of the whole into globules more or 

 less spherical and varying in size, suspended in the serum. Very 

 little of the cytoplasma is found in connection with these globules, 

 for, while the nucleus is passing through the conditions described, the 

 cytoplasma granulates and becomes dissolved in the serum. 



Such is the fate of the fusiform corpuscle when it lies by itself 

 When, however, it meets with another the two fuse, either by their 

 ends, as is commonly the case, or by their sides, and this capacity 

 for fusion may be exercised so much that small masses of them (white 

 thrombi) exist here and there over the field of the preparation. The 

 fusion is complete, all the lines of demarcation disappearing, even the 

 granules which formed the protoplasmic periphery being dissolved. 



These corpuscles are free from color and are like the leucocytes in 

 many respects. From the latter they are distinguished by the absence 

 of true amoeboid movement and by their regular shape and size. 



