122 On Fossil Infusoria, discovered in Peat-carth, 
tures are at times mentioned as plants, at times as animals, and fnbal 
under quite different denominations. 
“ Morren, in the highly important memoir on the Closterie,t has very 
fully treated the question, whether they should be arranged with animals 
or vegetables; he succeeded by employing very high magnifying powers, © 
in showing that those red and very movable little points discovered by. 
Ehrenberg at the ends of. these beings, were nothing else than minute 
- vesicles which afterwards change into new individuals. It was these 
eo BS and as it were, oscillating points, which were considered as or- 
s of motion, and appeared to justify the placing of the Closteri@ 
among animals, which, however, at present, after Morren’s discovery, falls 
to the ground. Besides the occurrence of these self-moving propagula in 
the interior of the Closterie, Morrem has observed a formation of fruit by 
conjugation, quite similar to the mode of formation of the fruit in the 
Conjugate,j and besides this there also net place an increase of the 
Closteria by separation. 
“The siliceous envelop which surrounds the Closteria, ‘as seal as all 
other Bacillaria, is regarded by Morren as a formation analogous to the so 
called cuticula at plants, a fact which is capable of confirmation only in 
certain relations ; for in the perfect plants this fine plate of silica lies in 
the substance of the cuticula, and is yonly separated from this by the de- 
Struction’of the organic parts. Besides this siliceous envelop, Morren 
supposes the existence of two other distinct membranes, which 
cuticles of the Closteriz, and inclose the green substance ; he however 
velop which is found in the members of Conferve when their spores are 
ripened, or they begin to increase in any other manner, as for instance, 
by excrescence and separation. © "Morten thinks it possible to explain the 
motion of the Closterie by the action of opposite electricities. The av- 
thor also gives a very complete description, accompanied by drawings, of 
the very manifold forms which the Closteria exhibit at different periods ; 
and by this he shows, how at least six of the new species of the genus 
Closterium, described by Ehrenberg, belong to one and the same species. 
: Brébisson§ also made observations on the enigmatical Diatome, 
in order to aeeidp the question, whether they should be ‘classed with ani- 
* Tam sorry to say, that these contradictions must abso eset? in this year’s report, 
as I do not think Ehrenberg’s view as to the animal nature of the Bacillarie weak- 
ened by the reasons here stated.—Wiegm 
_ + Sur les Clostéries, Ann. des Scienc. “Nat. "Vo 1. 3, p. 274. 
't The same observation bed been si by Conde —Also ay Ehrenbors in 
1834.— Wiegmann. 
§ Observations sur Ss Dianoashed: AJpetient de 1836, p. . 373. Ann. des Scien®- 
Nat., 1836, LU, p. 248. 
