On some Appearances, &c. By G. F. Dowdeswell. 527 



or spherical form, very variable iu size, from the most minute up 

 to nearly half that of a red blood-corpuscle ; these appear to be 

 the blood-plates of Bizzozero, and very possibly have an evolutional 

 significance : those of the other class, which more particularly relate 

 to the present subject, are always comparatively small, and more or 

 less irregular in form as above described. 



Though the bodies here in question — Max Schultze's cor- 

 puscles — are not mentioned in many treatises on microscopic 

 anatomy, yet as they appear to be always present in varying 

 numbers in the blood, whether they are evolutional or involu- 

 tional forms, they must be regarded as part of its normal 

 constituents ; and with respect to the subject here under con- 

 sideration, viz. investigation of the micro-organisms which occur in 

 these situations, must not be overlooked. The occurrence of the 

 mistake I have mentioned, which shows that they are not always 

 well known, where pre-eminently they ought to be so, has induced 

 me to refer to these bodies at some length. 



2. Proteid or Addison's processes of the red corpuscles. — The 

 next appearances which I have to mention, resemble Bacteria 

 far more closely than the former, indeed morphologically they are 

 indistinguishable from them ; they have been described by several 

 writers independently, in many cases apparently without knowing 

 what had been observed by others. In general, in a preparation of 

 blood under the Microscope, they appear first as small protuberances 

 or bud-like processes on the surface of the red corpuscles, very 

 similar to the first stage of gemmation in a yeast-cell ; these some- 

 times develope — as when the preparation is treated with a 5 per cent, 

 solution of ammonium chromate — to broad pseudopodial processes, 

 in some cases of comparatively considerable dimensions ; at other 

 times they form long fine filaments, apparently continuous, unseg- 

 mented, three oi^our times in length the diameter of the corpuscle, 

 of variable thickness, but frequently so fine as to be with difficulty 

 recognizable with the highest powers of the Microscope ; at other 

 times they form rosaries of minute spherules, similar to the torula 

 form of micrococci, or the spores of PeniciUium. In general they 

 very shortly become detached from the parent corpuscle, and may 

 then be observed free in molecular movement in the field of view, 

 simulating exactly Micrococci, Bacteria, or Bacilli; at other times 

 they are retracted within the plasma of the parent corpuscle. I 

 have previously regarded this occurrence as due to the spontaneous 

 contractility of the substance of the red-corpuscles, thereby shown 

 to be protoplasmic ; but I must here qualify that opinion, inasmuch 

 as it has lately been demonstrated in a very ingenious experiment, 

 by Haycraft, of Edinburgh,* that egg albumen, inclosed in an 

 indiarubber ball perforated with minute apertures, and placed in a 



♦ Prw. Rf.y. Soc. Edin., 1880-1, p. 29. 



