THE BLOOD-CORPUSCLES OF THE ANNELIDES. 493 



of his 'Icones Physiologicae ' (fig. 21), figures the blood-corpuscles 

 of the earthworm under three denominations, viz. firstly (a, b, 

 and <?), ' Korperchen mit vielen Vacuolen und stachlichen Fortsatze, 

 die Form und Stelle wechseln ; die Hohlraume mit gelblichem 

 Schimmer,' which amoebiform bodies I believe to be perivisceral 

 in origin ; secondly (d), ' Kerne,' one variety of which is granular, 

 and the other hyaline as to its contents ; and thirdly (e), ' Feine 

 Kornchen,' which till lately I held to be the only formed elements 

 existing in the worm's red fluid. But the two kinds of bodies 

 figured by Ecker at (d) are to be found in this fluid, when 

 uncontaminated with perivisceral fluid, and before its morphology 

 is upset by the setting in of those changes to which all fluids 

 containing colloids are so liable under the influence of so many 

 disturbing agencies. 



Thirdly, in the year 1835 we find Rudolph Wagner (Mtiller's 

 'Archiv/ 1835, p. 313) asserting a claim to having seen the 

 blood-corpuscles of the earthworm in 1832, and vindicating him- 

 self against an expression of surprise uttered by the elder Cams, in 

 his ' Lehrbuch der Vergleich. Zootomie' (ii. p. 682, 1834) at his not 

 having discovered the ' deutlichen runden abgeplatteten Blutkor- 

 perchen im rothen Blute des Regenwurmes/ 



Fourthly, Leydig's words ('Histologic/ p. 437, 1857), 'Zu 

 innerst sah man hoch vereinzelte blasse Kerne die wahrscheinlich 

 von Blutkugelchen bemhrten/ appear to me to apply, even when 

 I take the sentence in its own context alone, to the earthworm ; 

 and when I recollect that it was Ley dig who pointed out (' Archiv 

 fur Mikroskop. Anat.' i. 281, 1865) that Chaetogaster has no blood- 

 corpuscles, I cannot but think that he would have made here the 

 same remark as to Lumbricus if he had not seen it to be otherwise 

 conditioned, and indeed had not supposed himself to have stated 

 the fact to be so. 



Fifthly, I have to say that in the year 1861 the late Dr. John 

 Davy read a paper before the British Association at Manchester on 

 1 The Blood or Red Fluid of the Common Earthworm/ This 

 paper is printed in extenso in the second series of ' Physiological 

 Researches' (1863, pp. 203-207). In it Dr. Davy states that I 

 assisted him ' especially in laying bare the cardiac organs, and 

 in procuring their contents. 5 'Indeed/ he adds, ' it was at his 

 request that the inquiry was entered upon.' He then gives at 



