44?6 Mr. Weaver's View of Ehrenberg's Observations 



I showed, in 1837, that the Polythalamia could not well 

 possess an organization similar to that of the Infusoria, as not 

 a siu"le known true species of Infusoria has a calcareous shell ; 

 and I had, in 1823, discovered, as I conceived, a true living 

 Polythalamia of earlier authors, resembling in organization 

 the very complex Flustra. The correctness of this view was 

 fully established in 1839, after having examined anew, ac- 

 cording to my improved method, the small Nautilus Orbicu- 

 lus of Forskal, which d'Orbigny designated in 1826 as Num- 

 mulina {Assilina) ni.tida, specimens of which I had collected 

 from the sand of the Red Sea in 1823, and which I have 

 named Sorites Orhiculus. The result proved that the disc-like 

 shell was a Polypary, often composed of more than one hun- 

 dred single animalcules, the cells of which quite resemble those 

 of a Flustra, the animal putting forth and retracting from six to 

 eight tentacula. And I even discovered in the interior of the 

 sino-le cells well-preserved siliceous Infusoria, the last food 

 taken by the animal ; and in some of them also small globu- 

 lar bodies, which, without much constraint, may be considered 

 as eo-fTs, Though I had at an early period observed that the 

 disc was composed of many cells, yet I could not perceive an 

 opening to them; but the discovery of Infusoria in their in- 

 terior led me to consider by what means they could have been 

 introduced. Reflection reminded me that I had often seen 

 Coral animals which in the expanded state exhibited many 

 large bodies with tentacula and a large mouth, yet when con- 

 tracted left scarcely a trace of the openings through which 

 they were protruded from the common Polypary. As such I 

 remembered Fennatula, Lobularia, Halcyonium and similar 

 forms, in which I had frequently observed, that in the skin of 

 the animal existed calcareous particles, which on the contrac- 

 tion of the skin so completely closed the opening as to render 

 it no longer perceptible. Renewed examination of the closed 

 surface of the cells of the Nautilus Orhiculus, Forskal, now 

 showed to me that in them also dendritic calcareous particles 

 exist, the close approximation of which closes the cell, so that 

 the cover of the cell is in fact the dried skin of the animalcule. 

 I now made an experiment in proof, by dissolving the small 

 shell in dilute muriatic acid, in order to obtain the animal 

 body in a free state ; and it succeeded perfectly. I obtained 

 as many animalcular bodies as there were cells, connected to- 

 gether by band-like processes, and in the interior of many of 

 them there were well-preserved siliceous Infusoria, I then 

 treated in the same manner the Flustra pilosa and F. memhra- 

 nacca of the Baltic, and found in their interior also siliceous 

 Infusoria. The same results followed a similar examination 



