of the Red Blood CorpjLscle. 21 



the cell contents are crystallized within it ; and it is obvious that a 

 membranous envelope, which is equally distinct under the opposite 

 states of dryness and moisture, cannot be considered the result of 

 either condition. Again, perhaps it will be asserted, secondly, that 

 the appearances here presented might be simply the result of par- 

 tial crystallization in such a drop of viscid material as Professors 

 Fhnt and Beale consider the red blood disks, which drop, if the 

 process were complete, would have entirely assumed the crystalline 

 form ; but I think I can quite destroy the force of that or any 

 similar argument by the aid of other mounted preparations, some 

 of them showing that well-developed crystals, which happen to lie 

 in favourable positions, may include almost all the coloured portion 

 of the corpuscle, without in the least affecting the contour of its 

 cell wall. 



I regret exceedingly that the difficulty of obtaining and preserv- 

 ing the Menobranchus alive, has prevented me from attempting to 

 exhibit specimens of its fresh blood; but in the hope that other 

 microscopists will repeat and correct or confirm my researches 

 upon it, I am desirous of recording them and the conclusion which 

 they seem to involve. 



After a great many attempts, on which I spent altogether about 

 eight hours' steady work, I have twice succeeded in cutting a cor- 

 puscle in two with sharpened needles upon a stage of the micro- 

 scope, and beneath a half-inch objective, combined with a No. 2 

 eye-piece. On penetrating the vesicle with the edge of the needle, 

 its coloured contents were instantly evacuated, and disappeared at 

 once in the surrounding fluid, while the cell wall immediately 

 shrunk together, and became twisted upon itself, and around the 

 nucleus into a perfectly hyaUne particle, which showed some ten- 

 dency to adhere to the point of the instrument. It would there- 

 fore seem that the hasmato-crystallin was neither viscid nor semi- 

 solid, and that the cell wall was structureless, and possessed only 

 moderate tenacity, but of course the observations were too few in 

 number to be accepted as conclusive. 



When the corpuscles remained for two or three hours under 

 observation, those which did not crystalHze, often showed the 

 wrinkled appearance figured by Hassal in his Illustrations, and 

 described by Eollett, in Strieker's ' Handbuch der Lehre von den 

 Geweben,' Zweite Liefrung S. 286, and which seemed to me due to 

 the tendency of their colourless envelope, as the contained haemato- 

 crystallin condensed around the nucleus, to accommodate itself to 

 the diminished contents of the cell by falling into folds frequently 

 ramifying from the nuclear centre. When pressure was made by 

 means of a mounted needle upon the covering glass, almost directly 

 over a red disk, whose contents had undergone this contraction, 

 the first efiect was to round out the contour of the corpuscle, and 



