57 



chiefly to Bruch, Lieberkuhn, and A. Schmidt that the 

 honour of demonstrating this fact belongs. It is known also 

 that after a kind of cleavage of the granular masses of the 

 cysts these masses become transformed into little vesicles, 

 which in turn give rise to thepsorospermsorpseudo-navicells. 

 Lieberkuhn has shown that the psorosperms produce amoeboid 

 forms, and he thinks these amoebse themselves are developed 

 into Gregarinse, or give origin to Gregarinte. But this last 

 phase of the evolution of these little beings is still problema- 

 tical, and will require further serious investigation. But 

 what is perfectly established now, thanks to the labours of 

 Stein, Kolliker, Lieberkuhn, and several other naturalists, is 

 that there exists no relation of filiation whatever between the 

 Gregarinse and the Filarise, and that the opinion maintained 

 on this question by Henle, Bruch, and Leydig, must be 

 finally abandoned. 



I have not been able to observe these different phases of 

 the evolution of the Gregarinse of the lobster ; I have not 

 even succeeded in establishing the transformation of the 

 granular masses of the cysts into psorosperms ; but I have 

 fully recognised, in confirmation of the observations of Bruch, 

 Lieberkuhn, and A. Schmidt, that the contained granular 

 matter of the cysts is at first a simple sphere, always devoid 

 of nucleus, and that the two rounded masses which one 

 observes frequently in the cysts come from the first in conse- 

 quence of a sort of cleavage, in fact from a division. A groove 

 appears at first at the surface of the granular sphere, into 

 which the wall of the cyst immediat-ely is applied. This 

 fissure advances progressively towards the centre of the 

 sphere, and eventually divides it into two parts. Each of 

 them has the form of a hemisphere, and they are applied to 

 one another by their j)lane surface ; but soon the diameter of 

 the cyst increases, a space which is filled with a limpid, 

 colourless liquid as fast as it forms appears between the wall 

 of the cyst and the surface of the two granular masses, which 

 lose little by little their hemispherical form, becoming gra- 

 dually rounded. The diameter of the cyst continues to 

 increase, and the two masses at last become each a perfectly 

 spherical globe. I have seen all these changes take place on 

 the stage of the microscope. But what has not yet been 

 observed is, that after this division of the primitive sphere 

 into two spheres, the wall of the cyst formed by several con- 

 centric layers of a diaphanous material decomposes into a soft 

 granular matter, whilst each of the two globes surrounds 

 itself with a new membrane. Soon the traces of the envelope 

 ' Kollikei-'s ' Elements of Human Histolosv.' 



