3^48 Mr Cr G. Ehrcnberg's Observations on the 



loNOTROCHA 



rsiice dciimi^mtum, ore 



r > ^STASIA, Phytozoa rotatoria. Monotrocha ? Char. 

 Gen. Corpus varium cauaatum aut poi 



anticOy ciliis non distinctis, oculo nullo. 



It is very probable that this animalcule, which I call Astasia 

 Jicematodes, is one and the same with the Volvox lacustris of Girod 

 Chantran, but which seems to be still less changeable in its 

 forms, thence must iti the mean time be retained as Astasia 

 lacustris, A third form is probably the Astasia sanguinea, the 

 Enchelys sanguinea of Nees and Goldfuss. The structure of 

 this animal has a close affinity to the genus Eugkna, (Cerca- 

 ria viridis) that is furnished with an eye, which explains the cir- 

 cumstance why no propagation by division has been observed 

 among them, as is the case in the character of the class of ro- 

 t\ferous or wheel animals, I am acquainted with four distinct 

 species of the genus Euglena : E. viridis, Cere, viridis, M. E. 

 acus, Vibrio acus, M. E. pleur onectes, Cei'c,]^\euroriecteSj M. ; 

 and a new species, E. spirogyrmH'^^ ^nmfX 



Weber's animalcule may form a fifth species, as Euglena san- 

 guinea. No more zoological particulars belong to this place. 



I close the enumeration of my observations with the informa- 

 tion, that during this year at Berlin, the alga-form Sphceroplea 

 annulina, in the low lands at Kreutzberg towards Schonberg, 

 the flooded fields at the end of May appeared of a most beau- 

 tiful orange-colour, which passed into a lively cinnabar, to an 

 extent which I had never before witnessed. This algaform is 

 first green, hence the Sphceroplea scricea of Agardh refers to 

 the colour, which was occasioned by Bory de St Vincent's Cad" 

 mus sericeuSf which is just the earlier state of the same plant. 

 . A retrospect of all the facts regarding bodies which really or 

 apparently communicate a red or blood-like colour to waters and 

 a(jueous meteors, affords us the following catalogue of them. 

 . A. Blood-dew, Red-dew, Blood-rain, and lled-rain. 

 aoibod X^ Are deqi^edly shewn to be a deception caused 



3. By red atmospheric dust. 

 II. Are probably sometimes eff^ects of chemical processes, 

 producing red rain and red dew, but no particular 

 mstanccs supported by positive and undeniable 

 proof have been adduced by any one. 



