Monadina.] THE INFUSORIA. 95 



26. MONAS Dumalii. These animalcules, discovered by 

 M. Joly, are of a deep red colour. They occur in vast 

 numbers in the salt marshes of the Mediterranean, arid 

 give to those waters a deep blood colour. They are eaten 

 by a small Entomostracean, the Artemia salina. (Ann. 

 N. #.xxxvii. 317.) 



Genus II. UVELLA. The grape Monads. The species of 

 this genus are very well characterised by their aggregating 

 together occasionally, so as to form a grape or mulberry- 

 like mass, and by their generally possessing two (?) hair- 

 like proboscides at the mouth. Like the Monas, they are 

 deficient of the projecting lips, visual organ, and tail, and 

 have the mouth situated at the anterior extremity. They 

 progress also in the direction of the longest axis of their 

 body, and are endowed with the -capability of complete 

 self-division. There are six species two green, and the 

 remainder colourless. 



27. UVELLA viriscens. The yellowish- green Uvella 

 (Volvox uva, M.) Body ovate, and of the colour that 

 gives rise to its specific name. Found amongst conferva 

 and lemna. Size l-2000th; diameter of cluster l-280th. 



28. UVELLA chamaemorum. The colourless bramble- 

 berry Uvella* Smaller than the preceding one. Found in 

 water-butts. Size l-2880th; diameter of cluster 1-5 70th. 



29. UVELLA uva. The grape Uvella. Has indistinct 

 ventricles, and is very small. Found in stagnant water. 

 Size l-4800th; diameter of cluster 1 -960th. 



30. UVELLA atomus. The atom Uvella (Monas 

 atomus, M. lens et Volvox socialis, M.) Voracious, with 

 large ventricles. Size l-6900th to l-3406th; diameter 

 of cluster 1-1 150th. 



