P/dlvduKVa.'] INFUSORIAL ANIMALCULES. 673 



Phtlodina (•njthropthalma. — White and smooth, eyes round, horn- 

 like processes of the foot short, jaws two -toothed. This species is 

 common, and found abundantly dui'ing the spring and summer in water 

 tubs and amongst Conferva. In glass vessels it increases rapidly, and if 

 supplied occasionally with two or three stems of hay, the breed may 

 be preserved for j'cars. It is often met v/ith in vegetable infusions of 

 different kinds ; in these, however, it never originates, but only 

 inci'eases in number. Length l-120th to l-48th. 



P. roseola. — Eody smooth, eyes oval, horn-like processes of the 

 foot short. " I have obsei-ved," says Ekrcnberg, "that this animal- 

 cule, when kept in glasses, deposits its eggs in heaps, and the parent 

 remains a long time with the young ones produced from them, 

 forming a sort of family or colony, find which we are not to be hin- 

 dered from ascribing to a sense of company or family, though the 

 pride of man may laugh at it." Fig. 490 represents one with the 

 wheels extended. Length l-72nd to l-48th. 



P. collaris. — Is hyaline, or white, body smooth, eyes round, a pro- 

 minent annulus or collar surrounds the neck. It is especially 

 characterized by the extent of the alimentary canal, and coecal 

 appendages attached to it, so that, when the animalcule is fed upon 

 indigo, it appears like a polygastric animalcule. Length 1 -120th. 



P. macrostyla. — White and smooth, with oblong eyes ; it has three 

 teeth in each jaw ; horn-like processes of the base of the foot, long. 

 Found amongst Osciilatoria. Length l-70th. 



P. citrma. — Body smooth, citron-coloured in the middle, extremi- 

 ties white, eyes variable in form, horn-like processes sKghtly elongated. 

 Found amongst Osciilatoria. Length l-70th. 



P. aculeata. — Body white, provided mth soft spines, eyes round. 

 The respiratory tube is thickened anteriorly in a globose manner, the 

 jaws have each three teeth. Figs. 487, 488, represent this animalcule ; 

 and fig. 489, the jaws and teeth separate. Length l-70th. 



P. megalotrocha. — White, body smooth and short, wheels large ; 

 the proboscis between them long, eyes oval, and the jaws two-toothed. 

 Length 1-2 16th to l-108th. 



P. kirsuta. — Of a pale yellow colour, and covered by a short down ; 

 eyes oblong ; foot prolonged by dorsal spines, viviparous. Length 

 l-72nd; of egg, 1 -480th. Berlin. 



