20 Mr. H.J. Carter on the Development of Gonidia 



such an extent as to indicate the presence of the moving trans- 

 parent protoplasm. 



Thus the phsenomenon of motion in Zygnema, in Spongilla, 

 and in the Characese being exhibited by the same kind of sub- 

 stance, in organisms so nearly allied, and in instances where 

 there is evidently no direct connexion between it and the parent 

 plant, leads me to view it in all as modifications of one common 

 property, and that property a vital endowment of the same 

 nature as contractility or power of motion generally throughout 

 the animal kingdom. 



Bombay, January 1855. 



Postsciipt. — Since this paper was written, I have taken a dif- 

 ferent view of the nature of the so-called "gonidia^' in it, viz. 

 that they may be Infusoria, perhaps of the family Astasicea (Ehr.), 

 and that the " ciliated sacs " may have had a similar origin. 



Contrary to what Pringsheim has stated (Ann. and Mag. Nat. 

 Hist. vol. xi. 1853, p. 294 et seq.) respecting the integrity of 

 the cells of Spirogyra, wherein he witnessed a similar process of 

 development of gonidia to that which I have described above in 

 Nitella, viz. that a supposition of such gonidia being " foreign 

 structures, not belonging to the Spirogyray would be an altogether 

 inadmissible hypothesis, since they are formed in the interior of 

 the closed filament-cells of the Spirogyrse, directly from their con- 

 tents,'' &c. ; — contrary also to what I have myself stated above 

 respecting the formation of the same kind of gonidia in the cells 

 of Nitella, and where I might have also added that the cell-wall 

 did not show any signs of decay or unsoundness until the 

 " gonidia " were developed in the one instance, and the " ciliated 

 sacs '' in the other ; — I have nevertheless, from recent observa- 

 tions, been induced to doubt the correctness of this view. 



While examining some filaments of Conferva in which the 

 cells had become divided into resting spores, I perceived that 

 one of the capsules was so far empty, that it contained nothing 

 but a single large Astasia, which was filled with the chlorophyll 

 and other granules of the spore, part of which had turned 

 brown ; and although the capsule of the spore was fresh and the 

 vaginal sheath of the filament unruptured, there was a small 

 round hole in one part passing through both that was not more 

 than the l-4300th of an inch in diameter, and about which the 

 Astasia was lingering for the purpose of making its exit, but 

 having gorged the whole of the contents of the spore, this was of 

 course impossible. 



Here then was an infusorium with a transparent flask-shaped 

 sac terminated by a long cilium, distended by the granular con- 

 tents of the spore, and so incarcerated, that it must either die 



