STRUCTURE OF COLORED BLOOD-CORPUSCLES. 67 



cases constriction of portions more or less minute occurs, with 

 separation following constriction (see Fig. 21, e). Sometimes con- 

 stricted portions remain attached for a long time by a more or 

 less long and slender pedicle. Transitionally or permanently, in 

 any of the cases mentioned, the most curious and grotesque shapes 

 may be met with. In the cases, too, of constriction and separa- 

 tion, the corpuscles, with the portions attached and unattached, 

 sometimes gradually become rounded off so as to look like a 

 parent globule surrounded by a number of little ones. 



Secondly. Usually in the course of half an hour, the protrusion 

 of little round or roundish, more or less light colored, knobs takes 

 place. At first, only very few corpuscles show knobs, and the 

 knobs are extremely small and few in number, say only one, or 

 at most two or three, on a corpuscle ; but in the course of an 

 hour or two, more cor- 

 puscles protrude knobs, 

 more knobs are pro- 

 truded from one corpus- 

 cle, and the knobs grow 

 larger (Fig. 22, a). Occa- 

 sionally a knob is drawn 

 in again, and the former 

 contour reestablished. In 

 some instances protru- 

 sion and retraction occur 



repeatedly, SO that knobs 

 and 



FIG. 22. KNOB-FORMATION, PRINCIPALLY 

 BY PROTRUSION. 



a, Nos. I and 2, progressive and retrogressive protru- 



m* 8ion; No ' 3 * one P edunculated and tnree sessile knobs ; 



U.I NO. 4, detachment of two knobs; ft, protrusion of knobs 

 become larger and Small- at tne periphery and on the surface ; in No. 3, the knobs 

 , , , surround the whole body of the corpuscle ; and in No. 4, 



er, Very Slowly but repeat- they are still more numerous. 



edly, for some time. Oc- 



casionally a knob is pedunculated, and sometimes becomes de- 

 tached from the corpuscle, while, on the other hand, some knobs 

 are quite sessile. 



I have measured portions detached in either of the two ways 

 described, and found them to vary from the ^oWo to the ^^ of 

 an inch (.00084 .00338 mm.). All except the very largest may 

 usually be seen in constant oscillatory (molecular) movement, 

 and, unless entangled between larger stationary corpuscles, easily 

 moving across the field (the latter probably caused by minute vari- 

 ation from absolute equilibrium level of the microscope stage). 



In some dentated or so-called " mulberry" forms, knobs or 

 small eminences protrude from the face of the disk, which may 



