142 Ail Account of certain Organisms 



tion present a corpuscular appearance (PI. LXXIV., Fig. 1). There 

 are probably few observers in the habit of examining blood who 

 have not, at some time or other, met with these structures, and 

 have been puzzled for an explanation of their presence and nature. 



In size they vary greatly, from half or quarter that of a white 

 blood-corpuscle, to enormous masses occupying a large area of the 

 field, or even stretching completely across it. They usually assume 

 a somewhat round or oval form, but may be elongated and narrow, 

 or, from the existence of numerous projections, ofi'er a very irregular 

 outhne. They have a compact solid look, and by focussing are 

 seen to possess considerable depth ; while in specimens examined 

 without any reagents the filaments of fibrin adhere to them, and, 

 entangled in their interior, white corpuscles are not unfrequently 

 met with. 



It is not from every mass that a judgment can be formed of 

 their true nature, as the larger, more closely arranged ones have 

 rather the appearance of a granular body, and it is with difficulty 

 that the individual elements can be focussed. When, however, the 

 more loosely composed ones are chosen, their intimate composition 

 can be studied to advantage, especially at the borders, where only a 

 single layer of corpuscles may exist; and when examined with a 

 high power (9 or 10 Hartnack) these corpuscles are seen to be pale 

 round disks, devoid of granules and with well-defined contours. 

 Some of the corpuscles generally float free in the fluid about the 

 mass ; and if they turn half over, their profile view has the appear- 

 ance of a sharp dark line (Fig. 5, a and h). In water the indi- 

 vidual corpuscles composing the mass swell greatly; dilute acetic 

 acid renders them more distinct, while dilute potash solutions 

 quickly dissolve them. Measurements give, for the large propor- 

 tion of the corpuscles, a diameter ranging from -g^oVo^^h to roiTroth 

 of an inch ; the largest are as much as 5 oVo^h, and the smallest 

 from T5^T7oth to 2400 0th of an inch ; so that they may be said to 

 be from |th to ^ the size of a red corpuscle. In the blood of cats, 

 rabbits, dogs, guinea-pigs, and rats, the masses are to be found in 

 variable numbers. New-born rats are specially to be recommended 

 as objects of study, as in their blood the masses are commonly 

 both numerous and large. They occur also in the blood of foetal 

 kittens. 



Considering their prevalence in disease and among some of the 

 lower animals, they have attracted but little notice, and possess a 

 comparatively scanty literature. The late Professor Max Schultze * 

 was the first, as far as I can ascertain, to describe and figure the 

 masses in question. He speaks of them as constant constituents of 

 the blood of healthy individuals, but concludes that we know 

 nothing of their origin or destiny, suggesting, however, at the same 

 * Archiv f. mik. Auat., Bil. i. 



